Originally designed for the British nuclear disarmament movement by Gerald Holtom in 1958. Holtom drew himself when he was in a state of despair: with his palms stretched both outwards and downwards. The symbol is usually interpreted as a combination of the semaphore signals for the letters "N" and "D," standing for "nuclear disarmament".

nuclear proliferation
nuclear proliferation


Coordinate term: ∵


Abbreviation of French numéro, from Latin numerō (ablative of numerus).

der

ablative of <i class="Latn mention" lang="la">numerus</i>


(tennis) score after a player has scored one point in a game


A stylized representation of a scorpion with a stinging tail.

(astrology) The symbol for the sign Scorpio.

(astronomy, rare) The symbol for the constellation Scorpius.


German: ⁊c., ꝛc.

A stylized form of Latin et (“and”); part of the system of Tironian notes, shorthand popularly credited to Cicero’s scribe Marcus Tullius Tiro from first century BC. Compare to &, of same meaning and similar derivation. Despite the similar origin and same meaning the two symbols evolved separately from each other.

Now vnto yͤ king eternal, immortall, inuiſible, the onely wiſe God, be honour and glory for euer ⁊ euer. Amen.

1611, The Holy Bible, […] (King James Version) (in English), London: […] Robert Barker, […], →OCLC, 1 Timothy 1:17, column 2:


IM

(international standards) ISO 3166-1 alpha-2 country code for the Isle of Man since 2006.


(astrology) The symbol for the sign Aries.

(astronomy, rare) The symbol for the constellation Aries.


(tennis) A score after a player has scored three points in a game, one point away from winning the game.


Initialism of yen or initialism of yuan. The two lines represent the other two letters in the word 'yen'. One of the earliest uses of ¥ can be found in J. Twizell Wawn’s “Japanese Municipal Government With an Account of the Administration of the City of Kobe”, published in 1899. Usage of the sign increased in the early 20th century, primarily in Western English-speaking countries, but has also become commonly used in Japan as well.

The symbol for yen, the currency of Japan

The symbol for the yuan, the currency of China


A (copper/bronze) handmirror, symbol of the Greek goddess Aphrodite (and her Roman equivalent Venus). The cross was added in the 16th century to Christianize the symbol of a pagan god.

In his Mantissa Plantarum (1767) and Mantissa Plantarum altera (1771), [Linnaeus] regularly used ♂, ♀ and ☿ for male, female and hermaphrodite flowers respectively.

1961 August 17, New Scientist, volume 11, number 248 (in English), Reed Business Information, →ISSN, page 413:

Figure 2. Ossicones, secondary ossification, and sinuses of Giraffa: A Lateral aspect of skull showing courses of veins, areas of dense ossification (heavily stippled) and lesser secondary ossification (lightly stippled), and outlines of skull roofs of male (♂) and female (♀) adults.

1990, Charles S. Churcher, “Cranial Appendages of Giraffoidea”, George A. Bubenik, Anthony B. Bubenik, Horns, Pronghorns, and Antlers: Evolution, Morphology, Physiology, and Social Significance, New York: Springer-Verlag, chapter 1.5, page 183

I was quite surprised that a few of my friends found the male ♂ (mars) and female ♀ (venus) symbols on toilets in pubs/bars confusing ...

2015 July 6, Andy Burns, “Re: C4 last leg”, in uk.tech.broadcast (Usenet; in English):

(botany, of a flower) pistillate, carpellate.

Refers to the Latin phrase dies Veneris, which literally means "Venus's day".


(amateur radio, Morse code) "love"; "hugs and kisses"

amateur radio; Morse code; amateur radio; Morse code

Coordinate term: 1488

(neo-Nazism) Heil Hitler (H is the eighth letter of the alphabet.)


$ appears to have evolved circa 1775 in the United States from a common abbreviation for pesos, also known as piastres or pieces of eight, a P/raised-S ligature P^S. It was used in the US before the adoption of the dollar in 1785.
The "computing" sense is the result of homophony between English cache and cash, dollars being a form of cash.

A currency sign for the dollar, peso, and pataca.

An unofficial currency sign for the escudo.

(programming) Prefix indicating a variable in some languages, such as Perl, PHP, or shell scripts.


kdo

(international standards) ISO 639-5 language code for Kordofanian languages.


kde

(international standards) ISO 639-3 language code for Makonde.


ℎ

Max Planck wrote h for German Hilfsgrösse.

(physics) The symbol for Planck's constant.


t̼

A symbol of the IPA, representing a voiceless linguolabial plosive.


lim _(x→0⁺)1/x=+∞


ɐ

IPA

(IPA) a reduced near-open central vowel, undefined for rounding.

(superscript ⟨ᵄ⟩, IPA) [ɐ]-coloring or a weak, fleeting, epenthetic or echo [ɐ].

(superscript ⟨ᵄ⟩, UPA) an extremely short or fleeting ɐ.


√4̅ = √ = 2

The consonant of the reduplicating syllable is in general the first consonant of the root: thus, पप्रछ् paprach from √प्रछ् prach; शिश्रि çiçri from √श्रि çri; बुबुध् bubudh from √बुध्.

1889, W.D. Whitney, Sanskrit Grammar (in English), Breitkopf and Hartel, →OCLC, page 222:

Cratis = Reisig, Geflecht, Gitter, Schicht ist mit griech. κάρταλος = Korb, got. haúrds. nhd. Hürde u. s. w. von indog. √kerto = knüpfen, flechten abzuleiten ([…]), und hat sich auch mehrfach in den romanischen Sprachen erhalten, wie ital. grata = Gitter

1901, “Cratis”, in Paulys Realencyclopädie der classischen Altertumswissenschaft (in German), page 1682:

Cratis = brushwood, mesh, lattice, layer is along with Greek κάρταλος = basket, Gothic haúrds, New High German Hürde, etc. from Indo-European √kerto = to tie, braid ( […] ), and has also been preserved several times in the Romance languages, like Italian grata = lattice

Té̆rîtek ⵜⵔⵜⴾ (√ ⵔⵜⴾ ertek « tomber verticalement ») ‖ F.

1940, C. de Foucauld, Dictionnaire abrégé touareg-français de noms propres (in French), page 333:

Té̆rîtek ⵜⵔⵜⴾ (√ ⵔⵜⴾ ertek "fall vertically") ‖ F.

Ma questa particolare accezione di kawn non ha alcun nesso speciale con l'India, perchè è della lingua araba usare √ KWN ora per l'«essere» (come in كان اللّه) e ora per il «divenire», e il greco fa lo stesso con √ γεν e il sanscrito con √ bhū (bhava, mondo, كون; svabhâva, essenza, كيان).

1946, Annali lateranensi pubblicazione del Pontificio museo missionario etnologico, volume 3 (in Italian), page 197:

But this particular sense of kawn does not have anything special to do with India, because it is (characteristic) of Arabic to use √ KWN sometimes for "being" (as in كان اللّه) and sometimes for "becoming", and Greek does the same with √ γεν and Sanskrit with √ bhū (bhava, world, كون; svabhâva, essence, كيان).

Consider Israeli מיקום mikúm 'locating', from מקמ √mqm 'locate', which derives from biblical Hebrew מקום [må‿qom] 'place', whose root is קומ √qwm 'stand'

2010, A. Yadin, G. Zuckermann, “ […] Ideological Secularization of Hebrew Terms […] ”, in T. Omoniyi, editor, The Sociology of Language and Religion (in English), Springer, →ISBN, page 87:

Реконструированный корень √mā, разумеется, не являлся единственным выразителем значения ’расти’ в праиндоевропейском.

2013, Илья Якубович, Новое в согдийской этимологии (in Russian), Litres, →ISBN, page 104:

The reconstructed root √mā, of course, was not the only expression of the meaning 'to grow' in Proto-Indo-European.

Rekonstruirovannyj korenʹ √mā, razumejetsja, ne javljalsja jedinstvennym vyrazitelem značenija ’rasti’ v praindojevropejskom.

Gebildet zu einer Wurzel √fqh, zu der insbesondere auch ein Verb faqaha „verstehen, begreifen“ gehört.

2021, Utz Maas, “Die Stärke einer Sprache […] ”, in I.C. del Toro, E. Hack-Cengizalp, editors, Literalität und Mehrsprachigkeit (in German), →ISBN, page 15:

Formed from a root √fqh, which also includes a verb faqaha "to understand, comprehend".

(linguistics) Used before text to indicate it is a root.

Alternative spelling of ✓ (“check mark”)

An ad hoc symbol for the hypothetical Solar-system planet Vulcan


١

The Eastern Arabic numeral representing the number one.


१

From rotation of the curved, horizontal Nagari numeral with a small circle on the left, from curved Gupta variation of the flat, horizontal, third century BCE Brāhmī numeral (—).


Use as a multiplication sign is usually attributed to English mathematician William Oughtred.

7 × 8 = 56

{1,2} × {3,4} = {(1,3),(1,4),(2,3),(2,4)}

(set theory, category theory) Cartesian product, categorical product.

(1,2,5) × (3,4,−1) = (−22, 16, −2)

(linear algebra) Vector product, cross product.

Crocosmia × crocosmiiflora; Ursus maritimus × Ursus arctos

(taxonomy) Used in various ways to indicate hybridization between two or more different taxa.

Russ Millions × Tion Wayne

BAPE × Stüssy

2022 July 23, Gargi Harjai, “Where to buy the John Richmond × Playboy collection? Price, release date, and more explored”, in Sportskeeda (in English):

(music, fashion, etc.) Used to denote collaboration in the design, execution or branding of a piece.

The dimensions of the box are 60 cm × 60 cm × 52 cm.

Used to denote the geometric dimensions of an object.

2× as much soap as a regular bottle!

Apikalglied nicht besonders lang, beim Männchen etwa doppelt so lang wie das vorletzte Glied. [...] Beine lang und schlank. Das Basalglied der Hintertarsen 1,3× so lang wie die restlichen Glieder zusammen.

2011, Dmitry Telnov, Biodiversity, Biogeography and Nature Conservation in Wallacea and New Guinea: Volume 1 (in German), →ISBN, page 204:


vum

(international standards) ISO 639-3 language code for Vumbu.


bro

(international standards) ISO 639-3 language code for Brokkat.


r̃

A tilde over an r indicates that it is rolled/trilled, not flapped: r̃, R̃.

1996, Nicholas Awde, Hausa–English/English–Hausa Practical Dictionary (in English), Hippocrene Books, →ISBN, page vi:

The symbol r̃ (with the tilde diacritic) differentiates the alveolar tap/roll from the retroflex native flap r [ɽ], a phonemic contrast which is not marked in Hausa orthography (§16).

2001, Philip J. Jaggar, Hausa (in English), John Benjamins Publishing Company, →ISBN, page 8:

Hausa has two partially contrastive R sounds: a retroflex flap and a roll/tap. These are not distinguished in the standard orthography nor in Hausa written in Arabic script (termed ajami). In this dictionary (as well as in the companion English–Hausa Dicitonary and The Hausa Language), the difference between the two R’s is overtly marked as a pronunciation guide. (The distinction is, however, ignored for the purposes of alphabetization.) The flap R, e.g., rānā “sun”, is transcribed with the ordinary r symbol. The roll/tap R, e.g., r̃ahā̀ “pleasant chatting”, is written as r̃ (i.e., r with a tilde).

2007, Paul Newman, A Hausa–English Dictionary (in English), Yale University Press, →ISBN, page x:


ĵ

(phonetics, French) The affricate sound of English j.


ŝ

(phonetics, French) The affricate sound [t͡s].

(phonetics) The 'closed' voiceless fricative in Circassian for which ⟨ᵷ⟩ was once proposed for the IPA.


Ms

(metrology) Symbol for megasecond, an SI unit of time equal to 10⁶ seconds.


ĺ

(UPA) a palatalized or palatal l sound (IPA [lʲ] or [ʎ]), depending on the variant of UPA.


ɓ

IPA

(superscript ⟨𐞅⟩, IPA) a [ɓ]-release, such as ⟨ɠ𐞅⟩ for [ɠ͡ɓ]; [ɓ]-coloring; or a weak, fleeting or epenthetic [ɓ].


mar

(international standards) ISO 639-2 & ISO 639-3 language code for Marathi.


az

(international standards) ISO 639-1 language code for Azerbaijani.


ę

(phonetics) A nasal vowel [e]. The norm in Americanist notation; sometimes used in IPA transcription to leave room over the vowel letter for tone diacritics.


ǧ

(NAPA) a voiced postalveolar affricate (IPA [d͡ʒ]).


ć

(NAPA) a voiceless alveopalatal affricate (IPA [t͜ɕ]).


za

(international standards) ISO 639-1 language code for Zhuang.


yo

(international standards) ISO 639-1 language code for Yoruba.


tam

(international standards) ISO 639-2 & ISO 639-3 language code for Tamil.


aba

(international standards) ISO 639-3 language code for Abé.


WAN

w:ISO 3166-1 alpha-2#Indeterminate reservations

(international standards) Indeterminately reserved ISO 3166-1 alpha-3 country code for Nigeria.

International Organization for Standardization


toy

(international standards) ISO 639-3 language code for Topoiyo.


BOM

(international standards, aviation) IATA airport code for Chhatrapati Shivaji Maharaj International Airport, which serves Mumbai, India.


mat

(international standards) ISO 639-3 language code for Matlatzinca.


bin

(international standards) ISO 639-2 & ISO 639-3 language code for Edo.


CN

(international standards) ISO 3166-1 alpha-2 country code for China.


LT

(international standards) ISO 3166-1 alpha-2 country code for Lithuania since 1992.


More information
Invented by Louis Braille, braille cells were arranged in numerical order and assigned to the letters of the French alphabet. Most braille alphabets follow this assignment for the 26 letters of the basic Latin alphabet or, in non-Latin scripts, for the transliterations of those letters. In such alphabets, the first ten braille letters (the first decade: ⠁⠃⠉⠙⠑⠋⠛⠓⠊⠚) are assigned to the Latin letters A to J and to the digits 1 to 9 and 0. (Apart from '2', the even digits all have three dots: ⠃⠙⠋⠓⠚.)
The letters of the first decade are those cells with at least one dot in the top row and at least one in the left column, but none in the bottom row. The next decade repeat the pattern with the addition of a dot at the lower left, the third decade with two dots in the bottom row, and the fourth with a dot on the bottom right. The fifth decade is like the first, but shifted downward one row. The first decade is supplemented by the two characters with dots in the right column and none in the bottom row, and that supplement is propagated to the other decades using the generation rules above. Finally, there are four characters with no dots in the top two rows. Many languages that use braille letters beyond the 26 of the basic Latin alphabet follow an approximation of the English or French values for additional letters.

Braille eight-dot extensions from ⟨⠷⟩: ⡷ ⢷ ⣷


AQ

(international standards) ISO 3166-1 alpha-2 country code for Antarctica.


id

identity function
identity function#English

(international standards) ISO 639-1 language code for Indonesian.


nuo

(international standards) ISO 639-3 language code for Nguôn.


LC

(international standards) ISO 3166-1 alpha-2 country code for Saint Lucia.

(IUCN Red List) Abbreviation of Least Concern.


eke

(international standards) ISO 639-3 language code for Ekit.


NO

(chemistry) The molecular formula for nitric oxide.


NO

(international standards) ISO 3166-1 alpha-2 country code for Norway.


I can't see anything! – Hold on a second… *turns the light on

(Internet slang) Alternative form of * * (“encloses an interpretation”)

(computing) Used as a multiplication symbol; ×.

The string ab*c matches “ac”, “abc”, “abbc”, “abbbc”, and so on.

(regular expressions) Used as a wildcard to detect zero or more occurrences of the preceding element.

(algebra) Complex or transpose conjugate; conjugate.

In the language defined by AB*A, each string starts with an A, ends with a distinct A, and between them has zero or more Bs.

(algebra, computer science) Free monoid or Kleene star.

(linear algebra, functional analysis) Dual space.

(particle physics) Used to designate a resonance.

(IPA) a reserved symbol with no set meaning, that needs to be defined by the transcriber. May be used as a letter or as a diacritic.

Coordinate term: **

English prepositions come before the associated noun: we say She lives in Rome, not *She lives Rome in.

Roots like *bep- were not allowed in Proto-Indo-European.

(descriptive linguistics) Used before a term (such as a word, phrase, or sentence) to show that it is grammatically incorrect, or in some other way ill-formed.

Coordinate term: **

It is posited that Proto-Indo-European *sneygʷʰos is the etymon of both Latin nix and English snow.

His theory of the Proto-Slavic *kъniga being ultimately derived from Chinese, via the middle form *kūinig, reflecting ancient routes of cultural influx from the East, has not gained a firm ground in the Slavicist circles in the last century.

(historical linguistics) Used before or after a term to denote that it is only hypothesized and not actually attested.

When used before a term: that the term has been reconstructed by a linguist, on the basis of comparative method or by comparing other reconstructed terms, as the plausible ancestor form of an existing, attested term in one or more languages.

PIE *ḱonk- yielded Vedic śaṅk-ate “worries, hesitates”, as well as pre-Germanic *kank-, whence also Gothic hāhan* “to hang”.

When used after a term: that the term is actually attested, but not in its citation form that is being mentioned.

Proto-Germanic had three unvoiced fricatives: */f/, */þ/, and */h/.

When used before a symbol representing a phoneme: that the phoneme is reconstructed on the basis of comparative method.

Proto-Germanic had three unvoiced fricatives, possibly representing *[ɸ], *[θ], and *[x].

When used before a symbol representing a sound value: that the sound value is hypothesized.

(music) A pointing mark in Anglican chant, which marks a place in the text where an extra breath should be taken, resulting in a brief pause.


ita

(international standards) ISO 639-2 & ISO 639-3 language code for Italian.


res

mathematical analysis
mathematical analysis

(international standards) ISO 639-3 language code for Reshe.


ॐ

om or aum: the sacred syllable and mantra in Hinduism, Buddhism, Jainism and Sikhism


RP

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for the Philippines.


pus

(international standards) ISO 639-2 & ISO 639-3 language code for Pashto.


ä

(IPA) Sometimes used to transcribe an open central unrounded vowel, as ⟨a⟩ is officially an open front vowel.

(UPA) An open front unrounded vowel (IPA [æ]).

(superscript ⟨ᵃ̈⟩, UPA) an extremely short or fleeting ä.

n-year annuity-due to a person currently age x

äₓ

x5F;#x7B;k―}{̈{a_(x:◌̅n|)⁽ᵐ⁾|k-year deferred life annuity-due to a person currently age x, compounded m-thly}}


rap

(international standards) ISO 639-2 & ISO 639-3 language code for Rapa Nui.


NGN

(international standards) ISO 4217 currency code for the Nigerian naira.


lav

(international standards) ISO 639-2 & ISO 639-3 language code for Latvian.


ur

(international standards) ISO 639-1 language code for Urdu.


A cursive variation of ᾱ or ᾱᾱ, the abbreviation of Greek ἀνά (aná) used in recipes and prescriptions with the meaning "of each", and later extended to accounting. (Other explanations have that it is ā, an abbreviation of Latin ad (“to”), or French à (“to”).)

My e-mail address is psychonaut@example.com.

(computing) The symbol used as a separator between a username and a domain name in an e-mail address ("at" the domain name).

7 @ $2 = $14

seven, at two dollars each, are fourteen dollars

(computing, IRC) The most common choice of configurable prefix symbol to identify a channel operator.

Bob: How can I stop other people from accessing my files when they use my computer?

Jack: @Bob, you need to protect the files with a password.

(Internet) Prepended to the name of the user to whom a remark is addressed.

(phonetics) A pulse of laughter. (Thus @@@ is the transcription equivalent of ha! ha! ha! or hee! hee! hee! etc. in conventional orthography.)

While I was dealing with the hounds, an orc tracker stumbled across @ from the east.

(video games) In roguelike games, the player character, conventionally represented by this symbol in character-based interfaces.


cosh

(trigonometry) hyperbolic cosine, a hyperbolic function.


haw

(international standards) ISO 639-2 & ISO 639-3 language code for Hawaiian.


fro

(international standards) ISO 639-2 & ISO 639-3 language code for Old French.


ell

(international standards) ISO 639-2/T & ISO 639-3 language code for Greek.


amo

(international standards) ISO 639-3 language code for Amo.


reb

(international standards) ISO 639-3 language code for Rembong.


nob

(international standards) ISO 639-2 & ISO 639-3 language code for Norwegian Bokmål.


cog

(international standards) ISO 639-3 language code for Chong.


poi

(international standards) ISO 639-3 language code for Highland Popoluca.


raj

(international standards) ISO 639-2 & ISO 639-3 language code for Rajasthani.


mod

7 mod 2 = 1


ret

(international standards) ISO 639-3 language code for Retta.


pol

(international standards) ISO 639-2 & ISO 639-3 language code for Polish.


From Mandarin 閩南語／闽南语 (mǐnnányǔ, “Southern Min language”).

bor

(international standards) ISO 639-3 language code for Min Nan.


sou

(international standards) ISO 639-3 language code for Southern Thai.


tat

(international standards) ISO 639-2 & ISO 639-3 language code for Tatar.


mir

(international standards) ISO 639-3 language code for Isthmus Mixe.


tog

(international standards) ISO 639-2 & ISO 639-3 language code for Tonga (Malawi).


cam

(international standards) ISO 639-3 language code for Cèmuhî.


vie

(international standards) ISO 639-2 & ISO 639-3 language code for Vietnamese.


ana

(international standards) ISO 639-3 language code for Andaqui.


neb

(international standards) ISO 639-2 & ISO 639-3 language code for Toura.


hag

(international standards) ISO 639-3 language code for Hanga.


sag

(international standards) ISO 639-2 & ISO 639-3 language code for Sango.


IRL

(international standards) ISO 3166-1 alpha-3 country code for Ireland.


aap

(international standards) ISO 639-3 language code for Pará Arára.


TLC

(international standards, aviation) IATA airport code for Toluca International Airport, which serves Toluca, State of Mexico, Mexico.


yer

(international standards) ISO 639-3 language code for Tarok.


SF

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Finland.


cis

Abbreviation, presumably from either English cosine and sine and the number i or translingual cos, i, and sin.

(mathematics) The function cis(x)= cos x+i sin x.


GC

(metrology) Symbol for gigacoulomb, an SI unit of electric charge equal to 10⁹ coulombs.


GC

World Intellectual Property Organization

Gulf Cooperation Council Patent Office
w:GCC Patent Office

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for the Gulf Cooperation Council Patent Office.


Specified in ISO 216 of 1975, based on DIN 476, a German standardisation of 1921.

"There are preparations to be made for our guest's arrival," said Artemis, handing a typewritten sheet of A4 to Juliet.

2001, Eoin Colfer, Artemis Fowl, page 66:

The flat, befitting such a compromise, was stocked with two sizes of stationery: U.S. Letter and the thinner, taller A4 that is standard in Europe.

2006 June 5, Ben McGrath, “Eton on the F.D.R.”, in The New Yorker:

(international standards) ISO 216 standard paper size of 210 mm × 297 mm (8.27 in × 11.69 in), with a surface area of 624 cm² (96.7 sq in).


tut

(international standards) ISO 639-2 & ISO 639-5 language code for Altaic languages.


shy

(international standards) ISO 639-3 language code for Tachawit. The native name for the Shawiya language.


vav

(international standards) ISO 639-3 language code for Varli.


(logic) intensional disjunction, as in some relevant logics.

(mathematics) An operator indicating special-defined operation that is similar to addition.

(chemistry, obsolete) yttrium ("yttria", Daltonian symbol)


vau

(international standards) ISO 639-3 language code for Vanuma.


(Christianity, astronomy): A globus cruciger (the globe surmounted by a Christian cross), representing Christ's or the Church's rule over the redeemed world. Alchemical extension to newly-discovered antimony, motivated by an attempt to retain an association between the basic metals and the known planets. Astronomical use is reinforced by the graphic similarity to the symbol ⟨♀⟩ for Venus, which is the planet that is most similar to Earth.

(Christianity) the redeemed world (a symbol that was carried by depictions of Jesus and medieval Christian kings).

(alchemy) stibnite (antimony ore, Sb₂S₃).

(astrology, rare) the fictitious planet Proserpina, which one Polish school of astrology identifies as the dwarf planet Eris.


The lunar crescent is an ancient symbol for the moon.
Its orientation varies between increscent and decrescent.

rarely 🌙. In the medieval Marcianus graecus 299 manuscript

Night; nighttime; evening; twilight; darkness.

(astronomy, astrology, rare) The last quarter of the Moon.

(figurative) Change; transformation; transition.

graphical user interface
graphical user interface

(graphical user interface, signage) Do not disturb; quiet.

(graphical user interface, computing) Sleep mode; off.

(graphical user interface) Night mode: a colour scheme with light text on a dark background.

Refers to the Latin phrase dies Lunae, which literally means "Moon's day".


A simple caduceus (☤) of the Greek god Hermes (and his Roman equivalent Mercury), as seen with a much longer staff in stylized representations of that god e.g. on pottery. The cross was added in the 16th century to Christianize the symbol of a pagan god.

Refers to the Latin phrase dies Mercurii, which literally means "Mercury's day".

(Replaced by ⟨⚥⟩.)

In his Mantissa Plantarum (1767) and Mantissa Plantarum altera (1771), [Linnaeus] regularly used ♂, ♀ and ☿ for male, female and hermaphrodite flowers respectively.

1961 August 17, New Scientist, volume 11, number 248 (in English), Reed Business Information, →ISSN, page 413:

(botany, of a flower, obsolete) perfect, hermaphrodite.

The genders are typically represented by symbols derived from the planets. The female (Venus) and male (Mars) symbols (shown below) are commonly known and used.
Venus ♀ Mars ♂ Mercury ☿
As not everyone believes that they fit into either the male or female gender role regardless of their biological genetic sex, they tend to refer to themselves as the third category, intersex, intergender or transgender (see Mercury symbol above).

2012, Olga B. A. van den Akker, Reproductive Health Psychology (in English), John Wiley & Sons, →ISBN, page 40:

Ants like the honey-bees and one section of the wasps, are social insects with, in any well-established nest or community, three distinct forms—the perfect and fertile female (♀) the male (♂), and the so-called neuter or worker (☿), which is merely an undeveloped female.

1903, C. T. Bingham, Hymenoptera.—Vol. II. Ants and Cuckoo-wasps (The Fauna of British India, Including Ceylon and Burma) (in English), London: Taylor and Francis, page v:


The circle and arrow represent the shield and spear, respectively, of the Ancient Greek god of war Ares (and his Ancient Roman equivalent Mars). In the Medieval era the spear had crossed in front of the shield, and the ancient form lacked the shield altogether.

Figure 2. Ossicones, secondary ossification, and sinuses of Giraffa: A Lateral aspect of skull showing courses of veins, areas of dense ossification (heavily stippled) and lesser secondary ossification (lightly stippled), and outlines of skull roofs of male (♂) and female (♀) adults.

1990, Charles S. Churcher, “Cranial Appendages of Giraffoidea”, George A. Bubenik, Anthony B. Bubenik, Horns, Pronghorns, and Antlers: Evolution, Morphology, Physiology, and Social Significance, New York: Springer-Verlag, chapter 1.5, page 183

I was quite surprised that a few of my friends found the male ♂ (mars) and female ♀ (venus) symbols on toilets in pubs/bars confusing ...

2015 July 6, Andy Burns, “Re: C4 last leg”, in uk.tech.broadcast (Usenet; in English):

(the orbital period of Mars is 2 years)

Refers to the Latin phrase dies Martis, which literally means "Mars's day".


kaf

(international standards) ISO 639-3 language code for Katso.


mHz

(metrology) Symbol for millihertz, an SI unit of frequency equal to 10⁻³ hertz.


pH

Originally introduced in 1909 by S. P. L. Sørensen, using the notation p_(H⁺) for what he called the “hydrogen ion exponent” (Wasserstoffionenexponent ) of a solution. He may have chosen the symbol p arbitrarily; another suggestion is that it abbreviates German Potenz (“power”). The “H” is the international chemical symbol for the element hydrogen.

(chemistry) Measure of the acidity (low pH) or basicity (high pH) of an aqueous solution, equal to the negative logarithm of the concentration of hydronium ions in molars


pH

electrical inductance
electrical inductance

(metrology) Symbol for picohenry, an SI unit of electrical inductance equal to 10⁻¹² henrys.


waw

(international standards) ISO 639-3 language code for Waiwai.


bah

(international standards) ISO 639-3 language code for Bahamian Creole.


SOS

Chosen because its Morse code sequence (...---...) was easy to remember and recognize even through interference. Many mnemonics and backronyms were later formed from the sequence.


SOS

(international standards) ISO 4217 currency code for the Somali shilling.


irk

(international standards) ISO 639-3 language code for Iraqw.


kat

Symbol for katal, an SI unit of measurement of catalytic activity.

katal

(international standards) ISO 639-2/T & ISO 639-3 language code for Georgian.


tay

(international standards) ISO 639-3 language code for Atayal.


mai

(international standards) ISO 639-2 & ISO 639-3 language code for Maithili.


SN

(international standards) ISO 3166-1 alpha-2 country code for Senegal.


MGM

(international standards, aviation) IATA airport code for Montgomery Regional Airport, which serves Montgomery, Alabama, United States.


tai

(international standards) ISO 639-2 & ISO 639-5 language code for Tai languages.


oda

(international standards) ISO 639-3 language code for Odut.


aka

(international standards) ISO 639-2 & ISO 639-3 language code for Akan.


mon

(international standards) ISO 639-2 & ISO 639-3 language code for Mongolian.


STD

(international standards, historical) ISO 4217 currency code for the former first São Tomé and Príncipe dobra; a currency used from 1977 to 2018.


CV

(international standards) ISO 3166-1 alpha-2 country code for Cape Verde.


muu

(international standards) ISO 639-3 language code for Yaaku.


sip

(international standards) ISO 639-3 language code for Sikkimese.


SDP

(international standards, historical) ISO 4217 currency code for the former first Sudanese pound; a currency used from 1956 to 1998.


fi

(international standards) ISO 639-1 language code for Finnish.


nod

(international standards) ISO 639-3 language code for Northern Thai.


ii

From the transcription of Chinese 彝 (yí).

(international standards) ISO 639-1 language code for Nuosu.


ku

(international standards) ISO 639-1 language code for Kurdish.


dim

(international standards) ISO 639-3 language code for Dime.


rum

(international standards) ISO 639-2/B language code for Romanian.


ki

(international standards) ISO 639-1 language code for Kikuyu.


spa

(international standards) ISO 639-2 & ISO 639-3 language code for Spanish.


sui

(international standards) ISO 639-3 language code for Suki.


mis

(international standards) ISO 639-2 & ISO 639-3 language code for unencoded languages.


jul

(international standards) ISO 639-3 language code for Jirel.


mmm

(international standards) ISO 639-3 language code for Maii.


bov

(international standards) ISO 639-3 language code for Tuwuli.


que

(international standards) ISO 639-2 & ISO 639-3 language code for Quechuan.


nl

(metrology) Symbol for nanolitre, an SI unit of fluid measure equal to 10⁻⁹ litres.


nl

Clipping of Dutch Nederlands, the name of the Dutch language in Dutch.

clipping

Dutch <i class="Latn mention" lang="nl">Nederlands</i>

(international standards) ISO 639-1 language code for Dutch.


st

(international standards) ISO 639-1 language code for Sotho.


pl

(metrology) Symbol for picoliter (picolitre), an SI unit of fluid measure equal to 10⁻¹² liters (litres).

picoliter

(international standards) ISO 639-1 language code for Polish.


MV

(metrology) Symbol for megavolt, an SI unit of electromotive force equal to 10⁶ volts.


MV

(international standards) ISO 3166-1 alpha-2 country code for the Maldives.


SAT

Abbreviation of Boolean satisfiability problem.

abbrev

(computing theory) The decision problem of deciding whether a given Boolean formula has an assignment of Boolean values to its variables that makes it true. A famous NP-complete problem.


SAR

(international standards) ISO 4217 currency code for the Saudi riyal.


Introduced by Arend Heyting in “Die formalen Regeln der intuitionistischen Logik” (1930)

(x ≠ y) ↔ ¬(x = y)


ʆ

(obsolete, pre-1989 IPA) palatalized voiceless postalveolar sibilant fricative; now rendered as ⟨ʃʲ⟩ or ⟨ɕ⟩

(phonetics) The 'closed' voiceless fricative in Circassian, commonly transcribed ⟨ŝ⟩ and for which ⟨ᵷ⟩ was once proposed for the IPA.


(lexicography) indicates that a syllable may have either primary stress, /ˈ/, or secondary stress, /ˌ/.


(computing) A common prefix for escape characters.

Coordinate term: /

(computing) A pathname component separator in some operating systems, predominantly Microsoft ones.

\7 matches the 7th subexpression

(regular expressions) Matches what the nth marked subexpression matched using parentheses: ( ).


Used by writers and proof readers to indicate that something is missing.

n^2 = n² = n × n

2^n = 2ⁿ

Separates the base and exponent in a power expression.

exclusive disjunction
exclusive disjunction

(programming) Bitwise exclusive disjunction.

Press ^F to find text in your document.

(computing, as part of a keyboard shortcut) Control key.

^W = end of control block

control character
control character#English

(computing) Indicates an ASCII control character in caret notation.

^example$

(regular expressions) Matches the start position within the string. Compare $, which matches the end position within the string.

[^abc] matches any character other than "a", "b", or "c".

[^a-z] matches any single character that is not a lowercase letter from "a" to "z"

(regular expressions) Used with square brackets: [ ]. Matches a single character other than the characters and ranges specified between the square brackets.

Love Daisy Jones & the Six? Spending your free time deep-diving Fleetwood Mac drama? Suddenly need to know literally everything about Riley Keough, including how much she was paid for this show, not to mention her total net worth? Cool, same to literally ^ all ^ of ^ that.

2023 June 14, Mehera Bonner, “Riley Keough’s Net Worth Seems Kind of Complicated Due to the Elvis Estate”, in Cosmopolitan (in English):

(Internet slang) Used to point to a message (or other content) situated above in a forum, chat, etc.


(a,b]=x∈ R ,|,a<x<b

(mathematics) Denotes an open endpoint of an interval.


Typographical simplification, particularly due to the use of typewriters, thence followed in computers: rather than having separate opening (“) and closing (”) quotation marks (and other keys for ″ and others), a single square key was used, to reduce the number of keys.

〃 (ditto mark) Used in lists or tables to indicate a repetition of appropriate content above

(time, angles) An ASCII substitute for the symbol representing the second, placed after the value of the seconds in a term to indicate seconds count

Curved single quotation marks and apostrophes

Straight single quotation mark and apostrophe


[a,b)=x∈ R ,|,a<x<b


ZH

(metrology) Symbol for zettahenry, an SI unit of electrical inductance equal to 10²¹ henrys.


An abbreviated form of the virgula, ⟨/⟩, used to indicate a pause. The modern form was first used by Aldus Manutius. The virgula replaced the earlier dot because dots differentiated only by height were difficult to distinguish in medieval minuscule text.

I have 1,258 flags.

thousands separator
w:Thousands separator

In some counting systems, separates groups of three consecutive digits; the thousands separator.

Indian numbering system
w:Indian numbering system

In the Indian numbering system, separates groups of two consecutive digits, except for one final group of three.

Le debo 7,14 €. (Spanish)

J’ai payé 10,14 €. (French)

In some counting systems, sets off the decimal or fractional part of a number; the decimal separator.


From ᵒ/c, from Nᵒ/c, an abbreviation of Italian numero per cento (“number per hundred”). For the extension to Astraea is derived from the shift-5 key on the keyboard for asteroid (5).

der

10% is equal to 10 portions from 100.

For more than 90% of the figures (mostly drawn during 1976-1990), either a scale, or the given magnification, will allow the user to derive accurate measurements, even when these are lacking in the diagnosis.

1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, Chicago, Ill.: Field Museum of Natural History, →ISBN, page x:

Aldrichimica Acta Volume 30 No 4 (pdf) from Sigma-Aldrich
Decomposition of 4 in the presence of cis-piperylene at room temperature results in the stereocontrolled formation of trans-cycloheptadiene 27 in 90% ee (96% ee at −78 °C).

Indicates a portion from a total of a hundred.

(computing) Used as a wildcard, usually in SQL, to stand for zero or more characters.

(computing, programming) Used as the symbol for the modulus, placed between two numbers, to get the remainder of the division of those numbers.

(astrology, rare) The asteroid (5) Astraea.

uniform resource identifier
uniform resource identifier#English

(Internet) Used in the percent-encoding of uniform resource identifiers such as URLs.


WS

(international standards) ISO 3166-1 alpha-2 country code for Samoa.


zh

Clipping of Hanyu Pinyin zhōngwén, from Mandarin 中文 (Zhōngwén, “Chinese language”).

clipping

Hanyu Pinyin <i class="Latn mention" lang="cmn">zhōngwén</i>

der

(international standards) ISO 639-1 language code for Chinese.


Example, 3~10 = "3 to 10"; ~9 = "up to nine"; 50~ = "50 and greater."

In East-Asian languages, indicates a range of numbers

(mathematics) "is equivalent to"; "twiddles"

~p

(computing) user's home directory in Unix-like operating systems

black, adj: of the colour perceived in the absence of light. ~ eye: one that has been visibly bruised.

(lexicography) Replaces the headword in derivatives or example sentences, to save space.

(Internet slang) Appended to an utterance to indicate a flirty, playful tone.

Here are the three finest things to be had ~ a group supremé, in bathware. Sold everywhere in the United States ~ used ensemblé. They are in perfect harmony. Lanchère Blue Rose Bath Crystals dissolve quickly and at the same time release their fragrance.

1927 September 15, “For the bath”, in Vogue, Greenwich, Conn.: The Condé Nast Publications, Inc., page 189:

So Cremey! / Light or dark chocolate / Butter cremes / Raspberry / Lemon ~ Orange ~ Lime / Vanilla ~ Mint / $6.30 lb

1996 January 22, The Times-News, number 22, Twin Falls, Ida., page D-3, column 1:

2012, Tim Stump, Le Dernier Tour D'ivoire ~ Three Seasons Quick and Collected Poetry, →ISBN:


mid

(international standards) ISO 639-3 language code for Mandaic.


English: don't, y' , o'er (over), fo'c's'le (forecastle), tho' (though), cont'd (continued); German: Leut' (Leute)

Replaces one or more letters which have been removed from a written word, often but not always because they are not being pronounced.

English: I'm (I am), wouldn't've (would not have); French: qu’il (que il), à c’t’heure (à cette heure); German: gibt's (gibt es), auf'm (auf dem)

Replaces letter(s) when two or more words are contracted into one word.

'95 (1995)

Similarly replaces one or more numbers which have been removed.

An ASCII substitute for the foot (length unit symbol).

(mathematics) An ASCII substitute for ′ (prime symbol).

(time, angles) An ASCII substitute for the symbol representing the minute, placed after the value of the seconds in a term to indicate minutes count.

(music) A pointing mark in Anglican chant, which marks a place in the text where a barline occurs in the chant.


CP

w:ISO 3166-1 alpha-2#Exceptional reservations

Clipperton Island
Clipperton Island#English

(international standards) Exceptionally reserved ISO 3166-1 alpha-2 country code for Clipperton Island.


heb

(international standards) ISO 639-2 & ISO 639-3 language code for Hebrew.


ESA

(international standards, historical) ISO 4217 currency code for foreign-owned accounts in ordinary Spanish pesetas; a unit of account used until 1985.


WRT

(international standards, aviation) IATA airport code for Warton Aerodrome, which serves Warton, Lancashire, England.


mor

(international standards) ISO 639-3 language code for Moro.


sl

(international standards) ISO 639-1 language code for Slovene.

(General Alphabet of Cameroon Languages) a voiceless lateral fricative (IPA [ɬ]).


ABN

(international standards, aviation) IATA airport code for Albina Airstrip, which serves Albina, Suriname.


heh

(international standards) ISO 639-3 language code for Hehe.


DJ

(international standards) ISO 3166-1 alpha-2 country code for Djibouti since 1977.


nav

(international standards) ISO 639-2 & ISO 639-3 language code for Navajo.


alt

(international standards) ISO 639-2 & ISO 639-3 language code for Southern Altai.


BOB

(international standards) ISO 4217 currency code for the Bolivian boliviano.


GM

(international standards) ISO 3166-1 alpha-2 country code for Gambia.


USS

(international standards, historical) ISO 4217 currency code for the former United States dollar same-day funds; a unit of account used until 2014.


wad

(international standards) ISO 639-3 language code for Wandamen.


ps

(metrology) Symbol for picosecond, an SI unit of time equal to 10⁻¹² seconds.

picosecond

(international standards) ISO 639-1 language code for Pashto.


DNS

(international standards, aviation) IATA airport code for Denison Municipal Airport, which serves Denison, Iowa, United States.


elm

(international standards) ISO 639-3 language code for Eleme.


tig

(international standards) ISO 639-2 & ISO 639-3 language code for Tigre.


IR

(international standards) ISO 3166-1 alpha-2 country code for Iran.


ses

(international standards) ISO 639-3 language code for Koyraboro Senni.


acu

(international standards) ISO 639-3 language code for Shiwiar.


bas

(international standards) ISO 639-2 & ISO 639-3 language code for Basaa.


lb

(computer science): From New Latin logarithmus binarii (“binary logarithm”).

lb(x)= log ₂(x). lb(2)=1

(computer science) Binary logarithm; logarithm to the base 2.

(international standards) ISO 639-1 language code for Luxembourgish.


aan

(international standards) ISO 639-3 language code for Anambé.


kto

(international standards) ISO 639-3 language code for Kuot.


dum

(international standards) ISO 639-2 & ISO 639-3 language code for Middle Dutch.


wo

(international standards) ISO 639-1 language code for Wolof.


min

International System of Units
International System of Units

(metrology) minute in International System of Units

(international standards) ISO 639-2 & ISO 639-3 language code for Minangkabau.


vor

(international standards) ISO 639-3 language code for Voro.


ro

(international standards) ISO 639-1 language code for Romanian.


bg

(international standards) ISO 639-1 language code for Bulgarian.


lek

(international standards) ISO 639-3 language code for Leipon.


tab

(international standards) ISO 639-3 language code for Tabasaran.


(international standards) ISO 216 standard paper size of 297 mm × 420 mm (11.69 in × 16.54 in), with a surface area of 0.125 m² (1.34 sq ft).

Moody's Investors Service
w:Moody's Investors Service

(finance) Long-term bond credit rating by Moody's Investors Service, indicating that a bond is upper-medium grade with low risk of default.


zar

(international standards) ISO 639-3 language code for Rincón Zapotec.


CK

(international standards) ISO 3166-1 alpha-2 country code for the Cook Islands.


MCO

(international standards) ISO 3166-1 alpha-3 country code for Monaco.

(international standards, aviation) IATA airport code for Orlando International Airport, which serves Orlando, Florida, USA.


JFK

(international standards, aviation) IATA airport code for John F. Kennedy International Airport, which serves New York City, United States.


yup

(international standards) ISO 639-3 language code for Yukpa.


afa

(international standards) ISO 639-2 & ISO 639-5 language code for Afroasiatic languages.


RMB

According to statistics, not only the urban population but the population of nearby counties enjoys a net increase in disposable income. Net savings have also substantially increased. For instance, the population of Sanming accumulated a total savings of RMB 880 million, an increase of 8.2 times as compared with 1980.³⁷ Putian had total savings of RMB 441 million, a 10.2-fold increase over 1978.³⁸ Xiamen, Fujian’s most dynamic city had per capita savings of RMB 768, two times more than Sanming and Putian.³⁹

1996, C. Y. Chang, “Government and Politics”, in Brian Hook, editor, Fujian: Gateway to Taiwan (Regional Development in China), volume 2, Oxford University Press, →ISBN, →LCCN, →OCLC, page 51:

(international standards) Unofficial non-ISO 4217 currency code for the Chinese yuan. Initialism of renminbi.


BT

(international standards) ISO 3166-1 alpha-2 country code for Bhutan.


ie

(international standards) ISO 639-1 language code for Interlingue.


var

(international standards) ISO 639-3 language code for Huarijio.

(physics, electrics) Alternative form of VAR


The hyphen-minus, a catch-all symbol for certain dash and dash-like characters.


abc

(international standards) ISO 639-3 language code for Ambala.


vas

(international standards) ISO 639-3 language code for Vasavi.


vol

(international standards) ISO 639-2 & ISO 639-3 language code for Volapük.


alg

(international standards) ISO 639-2 & ISO 639-5 language code for Algonquian languages.


pK

dissociation constant
dissociation constant

(chemistry) the negative logarithm (to the base 10) of the dissociation constant of an electrolyte.

(chemistry) the pH at which equal concentrations of the acidic and basic forms of a substance are present.

thermodynamic temperature
thermodynamic temperature

(metrology) Symbol for picokelvin, an SI unit of thermodynamic temperature equal to 10⁻¹² kelvins.


IT

(international standards) ISO 3166-1 alpha-2 country code for Italy.


VD

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for North Vietnam from 1974 to 1976.


α

alpha

for names of this symbol in other language

fine structure constant
fine structure constant

(electrodynamics) The fine structure constant.

(in our Universe) a value of approximately 1/137 = 0.0072973525

See Wikipedia article on angular acceleration for usage.

angular acceleration
angular acceleration

(classical mechanics) Represents angular acceleration.

α-lactam has a three-membered ring structure.

chemical nomenclature
chemical nomenclature

(chemistry) Used in chemical nomenclature.

(astronomy) Used to identify some bright star, usually the brightest star, of a constellation, for instance α-Centauri.

(UPA) An open back rounded vowel (IPA [ɒ]).


STP

São Tomé and Príncipe
São Tomé and Príncipe#English

(international standards) ISO 3166-1 alpha-3 country code for São Tomé and Príncipe.


sem

(international standards) ISO 639-2 & ISO 639-5 language code for Semitic languages.


bod

(international standards) ISO 639-2/T & ISO 639-3 language code for Tibetan.


CLP

(international standards) ISO 4217 currency code for the Chilean peso.


km/h

(metrology) Kilometres/Kilometers per hour.


ADT

(international standards, aviation) IATA airport code for Ada Municipal Airport, which serves Ada, Oklahoma, United States.


KM

(international standards) ISO 3166-1 alpha-2 country code for the Comoros.


EA

(metrology) Symbol for exaampere, an SI unit of electrical current equal to 10¹⁸ amperes.


EA

Ceuta and Melilla
Ceuta and Melilla#English

(international standards) Exceptionally reserved ISO 3166-1 alpha-2 country code for Ceuta and Melilla.


amm

(international standards) ISO 639-3 language code for Ama.


asp

(international standards) ISO 639-3 language code for Algerian Sign Language.


tsi

(international standards) ISO 639-2 & ISO 639-3 language code for Tsimshian.


SME

w:ISO 3166-1 alpha-2#Indeterminate reservations

(international standards) Indeterminately reserved ISO 3166-1 alpha-3 country code for Suriname.


avu

(international standards) ISO 639-3 language code for Avokaya.


kpe

(international standards) ISO 639-2 & ISO 639-3 language code for Kpelle.


abs

(international standards) ISO 639-3 language code for Ambonese Malay.


kan

(international standards) ISO 639-2 & ISO 639-3 language code for Kannada.


ama

(international standards) ISO 639-3 language code for Amanayé.


bis

(international standards) ISO 639-2 & ISO 639-3 language code for Bislama.


ati

(international standards) ISO 639-3 language code for Attié.


ner

(international standards) ISO 639-3 language code for Yahadian.


SCO

(international standards, aviation) IATA airport code for San Francisco International Airport, which serves San Francisco, California, United States of America.


mdr

(international standards) ISO 639-2 & ISO 639-3 language code for Mandar.


ACK

(international standards, aviation) IATA airport code for Nantucket Memorial Airport, which serves Nantucket, Massachusetts, United States.


def

(international standards) ISO 639-3 language code for Dezfuli.


The symbol for the euro, the currency used by the European Monetary Union.


ℵ

Introduced by Georg Cantor, based on the Hebrew letter א, initial letter of אינסוף (infinity).

(set theory) Symbol for the transfinite enumeration of the infinite cardinal numbers in order of magnitude, a function mapping ordinal numbers to infinite cardinals.


kk

(international standards) ISO 639-1 language code for Kazakh.


kau

(international standards) ISO 639-2 & ISO 639-3 language code for Kanuri.


nm

(metrology) Symbol for nanometer (nanometre), an SI unit of length equal to 10⁻⁹ meters (metres).


Am

(climatology) Köppen climate classification for a tropical monsoon climate.


Bd

(computing) Symbol for baud, a unit of data transfer rate.


tib

(international standards) ISO 639-2/B language code for Tibetan.


Ar

relative atomic mass
relative atomic mass

(chemistry) The relative atomic mass of an element.


Ba

(physics) The CGS symbol for barye, unit of pressure.


Bi

(electricity, physics) biot (“abampere”)


Ca

(finance) Long-term bond credit rating by Moody's Investors Service, indicating that a bond is extremely speculative and possibly in default, with some prospect of debt recovery.


Ci

Symbol for curie, a unit of radioactivity.


Con

ZFC ⊨ Con(PA)

(mathematics, logic) consistency predicate


As

(climatology) Köppen climate classification for a dry-summer tropical savanna climate.


Eg

(metrology) Symbol for exagram, an SI unit of mass equal to 10¹⁸ grams.


tel

(international standards) ISO 639-2 & ISO 639-3 language code for Telugu.


Elm

(metrology) Symbol for exalumen, an SI unit of luminous flux equal to 10¹⁸ lumens.


Em

(metrology) Symbol for exameter (exametre), an SI unit of length equal to 10¹⁸ meters (metres).


El

(metrology) Symbol for exaliter (exalitre), an SI unit of fluid measure equal to 10¹⁸ liters (litres).


Es

(metrology) Symbol for exasecond, an SI unit of time equal to 10¹⁸ seconds.


Hg

From the New Latin hydrargyrum (“mercury”), form of hydrargyrus, from Ancient Greek ὑδράργυρος (hudrárguros, “quicksilver”), from ὕδωρ (húdōr, “water”) (whence hydro-) + ἄργῠρος (árguros, “silver”) (cognate to Ag (“symbol for silver”)). Compare quicksilver.


Gy

(metrology) The symbol for gray, a unit of absorbed dose.


Ga

(metrology) gigayears ago, a unit of time equal to 10⁹ years in the past.


Jy

(physics) Symbol for jansky, a unit of flux density.


KI

(chemistry) The molecular formula for potassium iodide.


KI

(international standards) ISO 3166-1 alpha-2 country code for Kiribati since 1979.


Ki

kibi- (binary kilo-), as in KiB kibibyte (kilobyte)


MHz

36 MHz transponder providing a pool of 794 reallocatable frequencies.

1976, James Martin, Telecommunications and the Computer:

(metrology) Symbol for megahertz, an SI unit of frequency equal to 10⁶ hertz.


Mg

(metrology) Symbol for megagram, an SI unit of mass equal to 10⁶ grams.


Mm

(metrology) Symbol for megametre (megameter), an SI unit of length equal to 10⁶ metres (meters).


Ml

(metrology) Symbol for megaliter (megalitre), an SI unit of fluid measure equal to 10⁶ liters (litres).


Ka

(chemistry) Symbol used to denote an acid dissociation constant.


Mu

(chemistry, physics) The chemical symbol for muonium (antimuon–electron pair pseudo-element; not the muon–antimuon onium pair (muononium))


Pg

(metrology) Symbol for petagram, an SI unit of mass equal to 10¹⁵ grams.


Pl

(metrology) Symbol for petaliter (petalitre), an SI unit of fluid measure equal to 10¹⁵ liters (litres).


Pa

(metrology) pascal, a unit of pressure and of stress.


PH

electrical inductance
electrical inductance

(metrology) Symbol for petahenry, an SI unit of electrical inductance equal to 10¹⁵ henrys.


PH

(international standards) ISO 3166-1 alpha-2 country code for the Philippines since 1974.


Ps

(metrology) Symbol for petasecond, an SI unit of time equal to 10¹⁵ seconds.


Re

Re(a + bi) = a

(mathematics) The real part of a complex number.


Sv

en:Harald Sverdrup (oceanographer)
en:Rolf Maximilian Sievert
en:Sv
en:Theodor Svedberg

* (sievert): From Swedish Sievert, named after Swedish medical physicist Rolf Maximilian Sievert
* (svedberg): From Swedish Svedberg, named after Swedish chemist Theodor Svedberg
* (sverdrup): From Norwegian Sverdrup, named after Norwegian oceanographer Harald Sverdrup

(metrology, SI) sievert, an International System of Units (SI) metric unit of radiation dose equivalent.

(metrology) svedberg, a non-SI metric unit of sedimentation.

(metrology) sverdrup, a non-SI metric unit of flow.


Te

(chemistry) Symbol for the element tellurium.


To

thoron; Obsolete form of Tn (“thoron”). (radon-220)


ka

The etymology for the ISO 639-1 code for Georgian is from Georgian ქართული ენა (kartuli ena).

(international standards) ISO 639-1 language code for Georgian.


Une

(chemistry) unnilennium, the former name of meitnerium.


Va

Because he had found six minima for every salt of virginium—VaCl, VaNO3, Va2SO4, and VaOH—he asserted that virginium consisted of a mixture of six stable isotopes.

2014, Marco Fontani, Mariagrazia Costa, Mary Virginia Orna, The Lost Elements: The Periodic Table's Shadow Side (in English), page 328:


Yg

(metrology) Symbol for yottagram, an SI unit of mass equal to 10²⁴ grams.


Zg

(metrology) Symbol for zettagram, an SI unit of mass equal to 10²¹ grams.


Uno

Abbreviation of New Latin unniloctium n.

(chemistry) Symbol for unniloctium, the former name of hassium.


Zs

(metrology) Symbol for zettasecond, an SI unit of time equal to 10²¹ seconds.


Π

∏ₙ₌₁⁴n²=1²·2²·3²·4²=576

Capital pi notation
w:Multiplication#Capital pi notation

(mathematics) Product over a set of like terms:

arithmetical hierarchy
arithmetical hierarchy

polynomial hierarchy
polynomial hierarchy

universal quantifier
universal quantifier

(mathematics, logic, computer science) A class (in some hierarchy of formulae, like the arithmetical hierarchy or polynomial hierarchy) of those formulae whose outermost quantifiers are universal quantifiers.


mA

(metrology) Symbol for milliampere, an SI unit of electrical current equal to 10⁻³ amperes.


Ο

originally used as a symbol for Big O notation, representing the asymptotic rate of growth of a function in mathematics


TS

electrical conductance
electrical conductance

(metrology) Symbol for terasiemens, an SI unit of electrical conductance equal to 10¹² siemens.


Bq

Symbol for the becquerel, an SI unit of radioactivity.


mN

(metrology) Symbol for millinewton, an SI unit of force equal to 10⁻³ newtons.


Å

Coordinate term: μ (micron)

(metrology) Symbol for angstrom/ångström.


kr

(international standards) ISO 639-1 language code for Kanuri.


sc

(international standards) ISO 639-1 language code for Sardinian.


mS

(metrology) Symbol for millisiemens, an SI unit of electrical conductance equal to 10⁻³ siemens.


mV

(metrology) Symbol for millivolt, an SI unit of electromotive force equal to 10⁻³ volts.


kW

(metrology) Symbol for kilowatt, an SI unit of power equal to 10³ watts.


Η

(textual criticism), the Alexandrian text-type (from Hesychius, its once-supposed editor).


fm

(metrology) The symbol for femtometer or femtometre, a unit of length. The name fermi for this unit is obsolete.


VAT

(international standards) ISO 3166-1 alpha-3 country code for the Vatican City.


bh

(international standards, obsolete) Former ISO 639-1 language code for Bihari.


pm

(metrology) Symbol for picometer (picometre), an SI unit of length equal to 10⁻¹² meters (metres).


nd

(international standards) ISO 639-1 language code for Northern Ndebele.


tl

(international standards) ISO 639-1 language code for Tagalog.


gd

(international standards) ISO 639-1 language code for Scottish Gaelic.


hs

(metrology) Symbol for hectosecond, an SI unit of time equal to 10² seconds.


pt

(international standards) ISO 639-1 language code for Portuguese.


COD

Democratic Republic of the Congo#English

(international standards) ISO 3166-1 alpha-3 country code for the Democratic Republic of the Congo since 1997.


TC

(metrology) Symbol for teracoulomb, an SI unit of electric charge equal to 10¹² coulombs.


TC

Turks and Caicos Islands
Turks and Caicos Islands#English

(international standards) ISO 3166-1 alpha-2 country code for the Turks and Caicos Islands.


Wb

International System of Units
International System of Units

The symbol for weber, the unit of magnetic flux in the International System of Units.


cs

(metrology) Symbol for centisecond, an SI unit of time equal to 10⁻² seconds.

centisecond

(international standards) ISO 639-1 language code for Czech.


rn

(international standards) ISO 639-1 language code for Kirundi.


ds

(metrology) Symbol for decisecond, an SI unit of time equal to 10⁻¹ seconds.


sm

(international standards) ISO 639-1 language code for Samoan.


Л

The Lobachevsky function, also referred to as an uppercase Lambda.


sr

(SI units) steradian (for measuring solid angles)

(international standards) ISO 639-1 language code for Serbian.


Mc

Abbreviation of moscovium. From Russian Москва́ (Moskvá, “Moscow”)

(chemistry) Symbol for moscovium (element 115, provisionally ununpentium).


br

(international standards) ISO 639-1 language code for Breton.


Ω

electrical resistance
electrical resistance

The symbol for ohm, the unit of electrical resistance in the International System of Units.


(rare) The symbol for peseta(s), Spanish currency until 2002.


A stylized combination of the Hebrew letters ש (sh) and ח (ḥ); see ש״ח (Sh.Ḥ.).

A currency sign representing the Israel new shekel.


The symbol for naira(s), the national currency of Nigeria.


From Korean 원(圓) (won), from Sinitic 圓／圆 (yuán, “circle; round coin”).

won(s), the national currency of South Korea.

won, the currency of the Kingdom of Korea.


The symbol for mill (s), which is 1/10 of a ¢ (cent).

for thousandth part generally, not currency specifically


PK

thermodynamic temperature
thermodynamic temperature

(metrology) Symbol for petakelvin, an SI unit of thermodynamic temperature equal to 10¹⁵ kelvins.


PK

(international standards) ISO 3166-1 alpha-2 country code for Pakistan.


Minimum registered capitalization of ฿2 million for foreign businesses operating non-restricted and ฿3 million for restricted businesses under the Foreign Business Act.

2022 July 11, Nelson P. Maranan, How to Operate an Outbound Recruitment Agency in Thailand (in English), Nelson P. Maranan, →ISBN:

A currency sign representing the Thai baht.

(proscribed) An unofficial currency sign representing bitcoin, primarily used before its symbol (₿) was added to Unicode.


MAC

(international standards) ISO 3166-1 alpha-3 country code for Macau.


F

From the Etruscan letter 𐌅 (v, “ve”), from the Ancient Greek letter Ϝ (W, “digamma”), derived from the Phoenician letter 𐤅 (w, “waw”), from the Egyptian hieroglyph 𓏲.

(biochemistry) IUPAC 1-letter abbreviation for phenylalanine

Coordinate term: G (“Birmingham gauge”)

synonyms: S for a sibilant fricative

(linguistics) A wildcard for a fricative

synonyms: more commonly HL, or more specifically HM or ML


mn

(international standards) ISO 639-1 language code for Mongolian.


yC

(metrology) Symbol for yoctocoulomb, an SI unit of electric charge equal to 10⁻²⁴ coulombs.


yT

magnetic flux density
magnetic flux density

(metrology) Symbol for yoctotesla, an SI unit of magnetic flux density equal to 10⁻²⁴ teslas.


B

A blood type that has a specific antigen that aggravates the immune response in people with type A antigen in their blood. They can receive blood from type B or type O, but cannot receive blood from AB or A.

hexadecimal 11

The eleventh item from the sequence {1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F}

The equivalent numbers of decimal 1611 are duodecimal B23, hexadecimal 64B, vigesimal 40B and so on.

Eleven, especially used in the base more than ten, such as duodecimal, hexadecimal, vigesimal and so on.

(biochemistry) As an IUPAC code for amino acids, aspartic acid or asparagine.

(linguistics) A wildcard for a labial consonant

(linguistics) low tone (e.g. in French-language text)

(finance) Long-term bond credit rating by S&P Global Ratings and Fitch Ratings, indicating that a bond is highly speculative with high risk of default.


zH

(metrology) Symbol for zeptohenry, an SI unit of electrical inductance equal to 10⁻²¹ henrys.


rog

(international standards) ISO 639-3 language code for Northern Roglai.


tg

In the sense of ISO 639-1 code, from Italian tagico.

trigonometric function
trigonometric function

(mathematics) The symbol of the trigonometric function tangent.

(international standards) ISO 639-1 language code for Tajik.


nb

(international standards) ISO 639-1 language code for Norwegian Bokmål.


L

From the Etruscan letter 𐌋 (l, “el”), from the Ancient Greek letter Λ (L, “lambda”), derived from the Phoenician letter 𐤋 (l, “lamed”), from the Egyptian hieroglyph 𓌅.

(biochemistry, IUPAC 1-letter abbreviation) leucine

(computer science) Deterministic logarithmic space

(astronomy, physics, measurement, cgs) lambert

(linguistics) A wildcard for a lateral or liquid consonant

(Voice Quality Symbols) position of the larynx (modified for raised, lowered)

(usually clothing) large (the manufactured size)


(card games) Symbol on playing cards for spades


(card games) Symbol on playing cards for diamonds


(card games) Symbol on playing cards for hearts

I♡NY

Stylistic substitution for the word love (or for its equivalent in another language).


cu

(international standards) ISO 639-1 language code for Old Church Slavonic.


ms

(metrology) Symbol for millisecond, an SI unit of time equal to 10⁻³ seconds.

millisecond

(international standards) ISO 639-1 language code for Malay.


abe

(international standards) ISO 639-3 language code for Western Abenaki.


ABA

(international standards, aviation) IATA airport code for Abakan International Airport, which serves Abakan, Khakassia, Russia.


D

* (chemistry, deuterium): abbreviation of deuterium
* (computing, hexadecimal 13): From its position as the thirteenth element of the series {1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F}
* (Germany): abbreviation of German word Deutschland (“Germany”)

(chemistry) Deuterium, when it needs to be distinguished from ordinary hydrogen.

(computing) Hexadecimal symbol for thirteen.

A standard size of dry cell battery larger than C.

Vehicle-distinguishing sign for Germany.

(biochemistry) IUPAC one-letter abbreviation for aspartic acid.

(mathematics) The differential operator in calculus and analysis.

(linguistics) A wildcard for an alveolar consonant

Moody's Investors Service
w:Moody's Investors Service

(finance) Long-term bond credit rating by Moody's Investors Service and S&P Global Ratings, indicating that a bond is in default, and the issuer is (or is about to become) bankrupt.

(actuarial notation) arithmetically decreasing payments


CG

Republic of the Congo
Republic of the Congo#English

(international standards) ISO 3166-1 alpha-2 country code for the Republic of the Congo.


pon

(international standards) ISO 639-2 & ISO 639-3 language code for Pohnpeian.


E

From the Etruscan letter 𐌄 (e, “e”), from the Ancient Greek letter Ε (E, “epsilon”), derived from the Phoenician letter 𐤄 (h, “he”), from the Egyptian hieroglyph 𓀠.

2E5 = 2 × 10⁵

(sciences, computing) Symbol separating mantissa from the exponent in scientific notation.

(biochemistry) IUPAC 1-letter abbreviation for glutamic acid

synonyms: I

(linguistics) A wildcard for a front vowel


EST

(international standards) ISO 3166-1 alpha-3 country code for Estonia since 1992.


J

From a modification of the Latin letter I (“i”), from the Etruscan letter 𐌉 (i, “i”), from the Ancient Greek letter Ι (I, “iota”), derived from the Phoenician letter 𐤉 (y, “yod”), from the Egyptian hieroglyph 𓂝.

(metrology) The symbol for joule, the unit of work or energy in the International System of Units

(linguistics) A wildcard for a palatal consonant

(Voice Quality Symbols) position of the jaw (modified for protruded, offset, etc.)


R

From the Etruscan letter 𐌓 (r, “er”), from the Ancient Greek letter Ρ (R, “rho”), derived from the Phoenician letter 𐤓 (r, “reš”), from the Egyptian hieroglyph 𓁶.

(currency symbol) Rand, national currency of South Africa.

Alcohols have the generic formula ROH.

(organic chemistry) An unspecified radical, usually containing a carbon atom that binds to the structure of interest.

(genetics) IUPAC 1-letter abbreviation for any purine.

(biochemistry) IUPAC 1-letter abbreviation for arginine.

synonyms: S for a sonorant

(linguistics) A wildcard for a rhotic consonant or a resonant (sonorant).

(linguistics) A wildcard for a rhotic archiphoneme, such as the conflation of /r/ and /ɾ/ in certain positions in Spanish.

synonyms: more commonly LH, or more specifically LM or MH

(finance) Long-term bond credit rating by S&P Global Ratings, indicating that a bond is extremely speculative and possibly in default, with some prospect of debt recovery.


ZAG

(international standards, aviation) IATA airport code for Zagreb Franjo Tuđman Airport, which serves Zagreb, Croatia.


G

From a modification of the Latin letter C (“ce”), from the Etruscan letter 𐌂 (c, “ce”), from the Ancient Greek letter Γ (G, “gamma”), derived from the Phoenician letter 𐤂 (g, “giml”), from the Egyptian hieroglyph 𓌙.

(biochemistry) glycine, a natural amino acid.

(biochemistry) Any of the nucleotides guanodine, nucleoside guanosine, or nucleobase guanine, which are components of DNA.

gravitational constant
gravitational constant

(physics) The gravitational constant in the formula F = Gm₁m₂/r²; sometimes called "big G" to distinguish from g for the acceleration of gravity.

(music) The major chord with a root of G.

Coordinate term: F (“French gauge”)

Birmingham gauge
Birmingham gauge#English

(medicine) Symbol for the Birmingham gauge.

(linguistics) A wildcard for a glide or semivowel


C

* (element symbol, carbon): abbreviation
* (metrology, coulomb): abbreviation
* (computing, hexadecimal 12): From its position as the twelfth element of the series {1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F}

(metrology) Symbol for coulomb, an SI unit of electric charge.

Alternative form: °C

Current commitments made by national governments under the Paris agreement fall far short of what is required – taken together, they would still condemn the world to an estimated temperature rise of more than 3C by the end of the century.

2019 December 2, Fiona Harvey, “Climate crisis: what is COP and can it save the world?”, in The Guardian:

(computing, hexadecimal) The digit for 12.

(genetics) IUPAC 1-letter abbreviation for any cytosine

(biochemistry) IUPAC 1-letter abbreviation for cysteine

C¹ functions are differentiable once, and C² functions are twice differentiable

∫ cos x,dx= sin x+C

constant of integration
constant of integration

(mathematics) The constant of integration.

(linguistics) A wildcard for a consonant

(Voice Quality Symbols) creak (vocal fry)

(finance) Long-term bond credit rating by Moody's Investors Service, indicating that a bond is in default, with little prospect of debt recovery.

(finance) Long-term bond credit rating by Fitch Ratings, indicating that a bond is low grade and on the verge of default.


N

From the Etruscan letter 𐌍 (n, en), from the Ancient Greek letter Ν (N, nu), derived from the Phoenician letter 𐤍 (n, nun), possibly from the Egyptian hieroglyph 𓆓.

When attacking, adhi drive opponents out of secure positions to make them vulnerable to gunfire or a concerted attack by the rest of the pack. Their jaw strength has been measured in excess of 1900 N, dangerous even when wearing a hardsuit.

2017, BioWare, Mass Effect: Andromeda, Redwood City: Electronic Arts, →OCLC, PC, scene: Outlaws: Adhi Codex entry:

(metrology) Symbol for newton, the SI unit of force.

(biochemistry) IUPAC 1-letter abbreviation for aspargine

(music) Neapolitan chord (usually in first inversion, therefore followed by a superscript six)

(linguistics) A wildcard for a nasal consonant (nasal stop)


P

From the Etruscan letter 𐌐 (p, “pe”), from the Ancient Greek letter Π (P, “pi”), derived from the Phoenician letter 𐤐 (p, “pe”), from the Egyptian hieroglyph 𓂋.

(biochemistry) IUPAC 1-letter abbreviation for proline

P(A) is the probability of A occurring

(computer science) class of problems solvable in polynomial time

synonyms: S for a 'stop'


V

From the Etruscan letter 𐌖 (u, “u”), from the Ancient Greek letter Υ (U, “ypsilon”), derived from the Phoenician letter 𐤅 (w, “waw”), from the Egyptian hieroglyph 𓏲. Doublet of Y and U.

The volt in the International System of Units.

(biochemistry) IUPAC 1-letter abbreviation for valine

(organic chemistry) The resin identification code for polyvinyl chloride, also PVC.

(Voice Quality Symbols) voice (modified for the kind of voice: 'nasal voice', 'harsh voice', etc.)


W

From a modification of the Latin letter V (“ve”), from the Etruscan letter 𐌖 (u, “u”), from the Ancient Greek letter Υ (U, “ypsilon”), derived from the Phoenician letter 𐤅 (w, “waw”), from the Egyptian hieroglyph 𓏲.
Its use as a symbol for tungsten is based on German Wolfram.

(biochemistry) IUPAC 1-letter abbreviation for tryptophan.

(historical) Wedgwood scale of temperature


K

From the Etruscan letter 𐌊 (k, “ka”), from the Ancient Greek letter Κ (K, “kappa”), derived from the Phoenician letter 𐤊 (k, “kap”), from the Egyptian hieroglyph 𓂧.

(chemistry) Symbol for potassium (Latin kalium).

Symbol for kelvin, the SI unit of thermodynamic temperature.

kelvin

(biochemistry) IUPAC 1-letter abbreviation for lysine.

hydraulic conductivity
hydraulic conductivity

(geology) Symbol for hydraulic conductivity.

5k = 5,000

(linguistics) A wildcard for a velar consonant

(linguistics) A wildcard for a consonant (e.g. in German-language texts)


Y

A late borrowing from the Ancient Greek letter Υ (U, “ypsilon”), first used to write Greek loanwords in Latin, derived from the Phoenician letter 𐤅 (w, “waw”), from the Egyptian hieroglyph 𓏲. Doublet of U and V.

(genetics) IUPAC 1-letter abbreviation for any pyrimidine

(biochemistry) IUPAC 1-letter abbreviation for tyrosine

reservation booking designator
reservation booking designator

(travel, aviation) The reservation booking designator for the highest level of economy air fare.

(mathematics, computer science) A Fixed-point combinator; especially Haskell Curry's combinator defined as λ f.(λ x.f (x x)) (λx.f (x x))


H

From the Etruscan letter 𐌇 (h, he), from the Ancient Greek letter Η (Ē, eta), derived from the Phoenician letter 𐤇 (ḥ, het), from the Egyptian hieroglyph 𓈈 or maybe 𓉗.

electrical inductance
electrical inductance

(physics) henry, a unit for measurement of electrical inductance in the International System of Units.

(biochemistry) IUPAC 1-letter abbreviation for histidine

(mathematics) Homology group or cohomology group

synonyms: Q for uvular consonants, Φ for pharyngeals

(linguistics) A wildcard for a glottal consonant or more broadly for a laryngeal consonant


Z

From the Etruscan letter 𐌆 (z, “ze”), from the Ancient Greek letter Ζ (Z, “zeta”), derived from the Phoenician letter 𐤆 (z, “zayin”), from the Egyptian hieroglyph 𓏭.

(physics) the impedance of an electrical circuit

(physics, computer graphics) the depth dimension in a 3D environment

(biochemistry) IUPAC 1-letter abbreviation for either glutamine or glutamic acid


T

From the Etruscan letter 𐌕 (t, “te”), from the Ancient Greek letter Τ (T, “tau”), derived from the Phoenician letter 𐤕 (t, “taw”), from the Egyptian hieroglyph 𓏴.

tesla, the SI unit of magnetic flux density.

(genetics) IUPAC 1-letter abbreviation for thymine

(biochemistry) IUPAC 1-letter abbreviation for threonine

(linguistics) a wildcard for a tone or stress level (the tonicity of a syllable)

(archaic, alchemy) a crucible [abbreviation of tigillum; see 🝨.]


U

From the Etruscan letter 𐌖 (u, “u”), from the Ancient Greek letter Υ (U, “ypsilon”), derived from the Phoenician letter 𐤅 (w, “waw”), from the Egyptian hieroglyph 𓏲. Doublet of Y and V.

(genetics) IUPAC 1-letter abbreviation for uracil

uniform distribution
uniform distribution

(mathematics, statistics) uniform distribution

synonyms: O

(linguistics) A wildcard for a rounded vowel or a back vowel

rack unit, the unit of length defined as 1.75 inches


kir

(international standards) ISO 639-2 & ISO 639-3 language code for Kyrgyz.


sam

(international standards) ISO 639-2 & ISO 639-3 language code for Samaritan Aramaic.


M

(astronomy) Abbreviation of Messier, used in Messier numbers.

(biochemistry) Abbreviation of methionine, as established by IUPAC.

(chemistry) Abbreviation of molar (one mole of substance per litre of solvent).

molar

mathematical analysis
mathematical analysis

(mathematical analysis) A generic manifold.

M_☉ — solar mass; M_🜨 — terrestrial mass; M_J or M_♃ — jovian mass; M_L or M_☾ — lunar mass

(astronomy) mass of a reference body as a unit of measure

(usually clothing) medium (the manufactured size)


ER

(international standards) ISO 3166-1 alpha-2 country code for Eritrea since 1993.


GU

(international standards) ISO 3166-1 alpha-2 country code for Guam.


LAX

(international standards, aviation) IATA airport code for Los Angeles International Airport, which serves Los Angeles, California, United States.


Q

English: max Q

Ancient Greek language
Egyptian language
Etruscan language
Phoenician language
Q

From the Etruscan letter 𐌒 (q, “cu”), from the Ancient Greek letter Ϙ (Q, “qoppa”), derived from the Phoenician letter 𐤒 (q, “qop”), from the Egyptian hieroglyph 𓃻.

(biochemistry) IUPAC 1-letter abbreviation for glutamine.

(logic, mathematics) Robinson arithmetic.

(sometimes covers any guttural consonant)

(linguistics) A wildcard for a uvular consonant.

(linguistics, Japanese) Gemination as a phoneme.


DD

From German Deutsche Demokratische Republik.

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for East Germany from 1974 to 1990.


DD

(finance) Long-term bond credit rating by Fitch Ratings, indicating that a bond is in default, with little prospect of debt recovery.

(IUCN Red List) Abbreviation of data deficient.

developmental disability
developmental disability#English

(medicine) Initialism of developmental disability.


S

From the Etruscan letter 𐌔 (s, “es”), from the Ancient Greek letter Σ (S, “sigma”), derived from the Phoenician letter 𐤔 (š, “šin”), from the Egyptian hieroglyph 𓌒.

electrical conductance
electrical conductance

(metrology) symbol for siemens, a measure of electrical conductance.

(metrology) symbol for spat (obsolete astronomical unit of distance).

(metrology) symbol for svedberg (unit of sedimentation rate in ultracentrifugation).

svedberg

(biochemistry) IUPAC 1-letter abbreviation for serine

(mathematics, computer science) The S ("substitution") combinator, defined as Sxyz = xz(yz), used in SKI calculus

(linguistics) A wildcard for a sibilant; or sometimes ambiguously for a stop, fricative, sonorant or semivowel

(usually clothing) small (the manufactured size)


GP

(international standards) ISO 3166-1 alpha-2 country code for Guadeloupe.


RE

(international standards) ISO 3166-1 alpha-2 country code for Réunion.


mo

(international standards, obsolete) Former ISO 639-1 language code for Moldovan.


BF

(international standards) ISO 3166-1 alpha-2 country code for Burkina Faso since 1984.


hei

(international standards) ISO 639-3 language code for Heiltsuk.


O

From the Etruscan letter 𐌏 (o, “o”), from the Ancient Greek letter Ο (O, “omikron”), derived from the Phoenician letter 𐤏 (ʿ, “ʿayin”), from the Egyptian hieroglyph 𓁹.

(mathematics) big O: a class of functions asymptotically bounded from above by a specific function, up to a constant factor

(linear algebra, group theory) orthogonal group

synonyms: U

(linguistics) A wildcard for a rounded vowel or a back vowel


AE

United Arab Emirates
United Arab Emirates#English

(international standards) ISO 3166-1 alpha-2 country code for the United Arab Emirates.


POA

(international standards, aviation) IATA airport code for Salgado Filho Porto Alegre International Airport, which serves Porto Alegre, Rio Grande do Sul, Brazil.


CU

(international standards) ISO 3166-1 alpha-2 country code for Cuba.


twp

(international standards) ISO 639-3 language code for Ere.


ADL

(international standards, aviation) IATA airport code for Adelaide Airport, which serves Adelaide, South Australia, Australia.


ADR

(international standards, aviation) IATA airport code for Robert F. Swinnie Airport, which serves Andrews, South Carolina, United States.


AAL

(international standards, aviation) IATA airport code for Aalborg Airport, which serves Aalborg, Denmark.


HR

(international standards) ISO 3166-1 alpha-2 country code for Croatia since 1992.


PUS

United States Miscellaneous Pacific Islands#English

(international standards, obsolete) Former ISO 3166-1 alpha-3 country code for the United States Miscellaneous Pacific Islands from 1974 to 1986.


PMI

(international standards, aviation) IATA airport code for Palma de Mallorca Airport, which serves Mallorca, Spain.


ZF

(metrology) Symbol for zettafarad, an SI unit of electrical capacitance equal to 10²¹ farads.


RCA

w:ISO 3166-1 alpha-2#Indeterminate reservations

Central African Republic
Central African Republic#English

(international standards) Indeterminately reserved ISO 3166-1 alpha-3 country code for the Central African Republic.


AAP

(international standards, aviation) IATA airport code for Aji Pangeran Tumenggung Pranoto International Airport, which serves Samarinda, East Kalimantan, Indonesia.


CRC

(international standards) ISO 4217 currency code for the Costa Rican colon.


IQ

(international standards) ISO 3166-1 alpha-2 country code for Iraq.


GE

(international standards) ISO 3166-1 alpha-2 country code for Georgia since 1992.

Gilbert and Ellice Islands
Gilbert and Ellice Islands#English

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for the Gilbert and Ellice Islands from 1974 to 1976.

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for the Gilbert Islands from 1976 to 1979.


EC

(metrology) Symbol for exacoulomb, an SI unit of electric charge equal to 10¹⁸ coulombs.


EC

(international standards) ISO 3166-1 alpha-2 country code for Ecuador.


RC

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Taiwan.


SOL

(international standards) Unofficial non-ISO 4217 currency code for the cryptocurrency Solana.


PV

(metrology) Symbol for petavolt, an SI unit of electromotive force equal to 10¹⁵ volts.


PT

magnetic flux density
magnetic flux density

(metrology) Symbol for petatesla, an SI unit of magnetic flux density equal to 10¹⁵ teslas.


PT

(international standards) ISO 3166-1 alpha-2 country code for Portugal.


CFN

(international standards, aviation) IATA airport code for Donegal Airport, which serves Carrickfinn, Ireland.


NPL

(international standards) ISO 3166-1 alpha-3 country code for Nepal.


OTL

An emoticon representing frustration or headdesk


IE

(international standards) ISO 3166-1 alpha-2 country code for Ireland.


JP

(international standards) ISO 3166-1 alpha-2 country code for Japan.


ibo

(international standards) ISO 639-2 & ISO 639-3 language code for Igbo.


GI

(international standards) ISO 3166-1 alpha-2 country code for Gibraltar.


GS

(metrology) Symbol for gigasiemens, an SI unit of electrical conductance equal to 10⁹ siemens.


GS

South Georgia and the South Sandwich Islands#English

(international standards) ISO 3166-1 alpha-2 country code for South Georgia and the South Sandwich Islands since 1993.


ACC

(international standards, aviation) IATA airport code for Kotoka International Airport, which serves Accra, Ghana.


BMD

(international standards) ISO 4217 currency code for the Bermudian dollar.


BW

(international standards) ISO 3166-1 alpha-2 country code for Botswana.


INR

(international standards) ISO 4217 currency code for the Indian rupee.


DOP

(international standards) ISO 4217 currency code for the Dominican peso.


AED

(international standards) ISO 4217 currency code for the United Arab Emirates dirham.


AMD

(international standards) ISO 4217 currency code for the Armenian dram.


AOA

(international standards) ISO 4217 currency code for the Angolan kwanza.


EP

European Patent Organisation
w:European Patent Organisation

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for the European Patent Organisation.


KP

(international standards) ISO 3166-1 alpha-2 country code for North Korea.


MAD

(international standards) ISO 4217 currency code for the Moroccan dirham.


ABS

(international standards, aviation) IATA airport code for Abu Simbel Airport, which serves Abu Simbel, Aswan, Egypt.


ALA

(international standards) ISO 3166-1 alpha-3 country code for Åland since 2004.


LSM

(international standards, obsolete) Former ISO 4217 currency code for the Lesotho loti.


ATF

Adélie Land
Antarctica
French Southern and Antarctic Lands

French Southern Territories
French Southern Territories#English

(international standards) ISO 3166-1 alpha-3 country code for the French Southern Territories since 1979.

French Southern and Antarctic Lands#English

(international standards, obsolete) Former ISO 3166-1 alpha-3 country code for the French Southern and Antarctic Lands from 1974 to 1979.


RHD

(international standards, historical) ISO 4217 currency code for the former Rhodesian dollar; a currency used from 1970 to 1980.


AON

(international standards, historical) ISO 4217 currency code for the former Angolan novo kwanza; a currency used from 1990 to 1995.


SLE

(international standards) ISO 3166-1 alpha-3 country code for Sierra Leone.

(international standards) ISO 4217 currency code for the new Sierra Leonean leone.


DOT

(international standards) Unofficial non-ISO 4217 currency code for the cryptocurrency Polkadot.

Dominican Republic
ISO 3166-1 alpha-2
ISO 4217


ACS

(international standards, aviation) IATA airport code for Achinsk Airport, which serves Achinsk, Krasnoyarsk Krai, Russia.


ACE

(international standards, aviation) IATA airport code for César Manrique-Lanzarote Airport, which serves Lanzarote, Las Palmas.


diag

(linear algebra) a function that takes an n-element vector a and outputs an n by n diagonal matrix A where A_ii=a_i


chk

Might be a Clipping of English Chuukese, but might also be from its earlier form of Chuukese chuk (mountain), from which the word "Chuukese" is derived.

clipping

English <i class="Latn mention" lang="en">Chuukese</i>

(international standards) ISO 639-2 & ISO 639-3 language code for Chuukese.


MGF

(international standards, historical) ISO 4217 currency code for the former Malagasy franc; a currency used from 1963 to 2004.


JT

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for Johnston Atoll from 1974 to 1986.


DO

Dominican Republic
Dominican Republic#English

(international standards) ISO 3166-1 alpha-2 country code for the Dominican Republic.


TRV

(international standards, aviation) IATA airport code for Thiruvananthapuram International Airport, which serves Thiruvananthapuram, Kerala, India.


PL

(metrology) Symbol for petaliter (petalitre), an SI unit of fluid measure equal to 10¹⁵ liters (litres).


PL

(international standards) ISO 3166-1 alpha-2 country code for Poland.


ANG

(international standards) ISO 4217 currency code for the Netherlands Antillean guilder.


PRT

(international standards) ISO 3166-1 alpha-3 country code for Portugal.


LF

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Fezzan.


RH

(international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Haiti.

Southern Rhodesia
Southern Rhodesia#English

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for Southern Rhodesia from 1974 to 1980.


CR

(international standards) ISO 3166-1 alpha-2 country code for Costa Rica.

Critically Endangered
w:Critically Endangered

(IUCN Red List) Abbreviation of Critically Endangered.


BR

(international standards) ISO 3166-1 alpha-2 country code for Brazil.


AF

(international standards) ISO 3166-1 alpha-2 country code for Afghanistan.


MLI

(international standards) ISO 3166-1 alpha-3 country code for Mali.


exp

exp(x) = eˣ

exponential function
exponential function


ESP

(international standards) ISO 3166-1 alpha-3 country code for Spain.

(international standards, historical) ISO 4217 currency code for the former Spanish peseta; a currency used from 1868 to 2002.


TD

(international standards) ISO 3166-1 alpha-2 country code for Chad.


MH

electrical inductance
electrical inductance

(metrology) Symbol for megahenry, an SI unit of electrical inductance equal to 10⁶ henrys.


MH

Marshall Islands
Marshall Islands#English

(international standards) ISO 3166-1 alpha-2 country code for the Marshall Islands since 1986.


QA

(international standards) ISO 3166-1 alpha-2 country code for Qatar.


SU

special unitary group
special unitary group


SU

(international standards, obsolete) Former ISO 3166-1 alpha-2 country code for the Soviet Union from 1974 to 1992.

w:ISO 3166-1 alpha-2#Exceptional reservations

(international standards) Exceptionally reserved ISO 3166-1 alpha-2 country code for the Soviet Union.


meo

(international standards) ISO 639-3 language code for Kedah Malay.


PES

(international standards, historical) ISO 4217 currency code for the former first Peruvian sol; a currency used from 1863 to 1985.


I

From the Etruscan letter 𐌉 (i), from the Ancient Greek letter Ι (I, iota), derived from the Phoenician letter 𐤉 (y, yod), from the Egyptian hieroglyph 𓂝.

(physics, electronics) Electrical current.

(physics, kinematics) moment of inertia.

(biochemistry) IUPAC 1-letter abbreviation for isoleucine

(mathematics, linear algebra) identity matrix

mathematical analysis
mathematical analysis

(mathematical analysis, topology) the (closed) unit interval; [0, 1]

(inorganic chemistry) Specifying an oxidation state of 1

synonyms: E for a front vowel, Ɨ for a high vowel

(linguistics) A wildcard for a front vowel or a high vowel

(actuarial notation) arithmetically increasing payments


STN

(international standards) ISO 4217 currency code for the São Tomé and Príncipe dobra.

(international standards, aviation) IATA airport code for London Stansted Airport, which serves London, United Kingdom.


fl

(metrology) Symbol for femtoliter (femtolitre), an SI unit of fluid measure equal to 10⁻¹⁵ liters (litres).


MRO

(international standards, historical) ISO 4217 currency code for the former first Mauritanian ouguiya; a currency used from 1973 to 2018.


hr

Clipping of Serbo-Croatian hrvatski / хрватски

(international standards) ISO 639-1 language code for Croatian.


GF

(metrology) Symbol for gigafarad, an SI unit of electrical capacitance equal to 10⁹ farads.


GF

(international standards) ISO 3166-1 alpha-2 country code for French Guiana.


PRI

(international standards) ISO 3166-1 alpha-3 country code for Puerto Rico.


mth

(international standards) ISO 639-3 language code for Munggui.


SS

(international standards) ISO 3166-1 alpha-2 country code for South Sudan since 2011.


DOM

(international standards) ISO 3166-1 alpha-3 country code for the Dominican Republic.


RSM

w:ISO 3166-1 alpha-2#Indeterminate reservations

(international standards) Indeterminately reserved ISO 3166-1 alpha-3 country code for San Marino.


DMA

(international standards) ISO 3166-1 alpha-3 country code for Dominica.


ann

(international standards) ISO 639-3 language code for Obolo.


GD

(international standards) ISO 3166-1 alpha-2 country code for Grenada.


aud

(international standards) ISO 639-3 language code for Anuta.


ch

Alternative form of cosh (“hyperbolic cosine”)

(international standards) ISO 639-1 language code for Chamorro.


num

(international standards) ISO 639-3 language code for Niuafo'ou.


ces

(international standards) ISO 639-2/T & ISO 639-3 language code for Czech.


nat

(international standards) ISO 639-3 language code for Hungworo.


int

(international standards) ISO 639-3 language code for Intha.


SVG

(international standards, aviation) IATA airport code for Stavanger Airport, Sola, which serves Stavanger, Norway.


LBP

(international standards) ISO 4217 currency code for the Lebanese pound.


CHF

Abbreviation of Latin Confoederationis Helveticae (“of the Swiss Confederation”) + Latin francus (“franc”).

der

(international standards) ISO 4217 currency code for the Swiss franc.


lib

(international standards) ISO 639-3 language code for Likum.


AMS

(international standards, aviation) IATA airport code for Amsterdam Airport Schiphol, which serves Amsterdam, Netherlands.


USD

(international standards) ISO 4217 currency code for the United States dollar.


CCC

(finance) Long-term bond credit rating by S&P Global Ratings, indicating that a bond is low grade with extremely high risk of default.

(finance) Long-term bond credit rating by Fitch Ratings, indicating that a bond is low grade with very high risk of default.


IST

(international standards, aviation) IATA airport code for Istanbul Airport, which serves Istanbul, Turkey.


BO

(international standards) ISO 3166-1 alpha-2 country code for Bolivia.


adj

(international standards) ISO 639-3 language code for Adioukrou.


TCA

Turks and Caicos Islands
Turks and Caicos Islands#English

(international standards) ISO 3166-1 alpha-3 country code for the Turks and Caicos Islands.


AAS

(international standards, aviation) IATA airport code for Apalapsili Airport, which serves Apalapsili, Papua, Indonesia.


hu

(international standards) ISO 639-1 language code for Hungarian.


YK

thermodynamic temperature
thermodynamic temperature

(metrology) Symbol for yottakelvin, an SI unit of thermodynamic temperature equal to 10²⁴ kelvins.


NR

(international standards) ISO 3166-1 alpha-2 country code for Nauru.


ž

(NAPA) a voiced postalveolar fricative (IPA [ʒ]).

Ǎǎ Čč Ďď Ěě Ǧǧ Ȟȟ Ǐǐ J̌ǰ Ǩǩ Ľľ Ňň Ǒǒ Řř Šš Ťť Ǔǔ Ǚǚ Žž Ǯǯ DŽDždž Ǆǅǆ


AO

(international standards) ISO 3166-1 alpha-2 country code for Angola.


PW

(metrology) Symbol for petawatt, an SI unit of power equal to 10¹⁵ watts.


PW

(international standards) ISO 3166-1 alpha-2 country code for Palau since 1986.


DDR

(international standards, obsolete) Former ISO 3166-1 alpha-3 country code for East Germany from 1974 to 1990.


RFD

(international standards, aviation) IATA airport code for Chicago Rockford International Airport, which serves Chicago, Illinois, United States.


tr

(international standards) ISO 639-1 language code for Turkish.

(mathematics) The symbol for the trace function on square matrices.


TT

magnetic flux density
magnetic flux density

(metrology) Symbol for teratesla, an SI unit of magnetic flux density equal to 10¹² teslas.


TT

Trinidad and Tobago
Trinidad and Tobago#English

(international standards) ISO 3166-1 alpha-2 country code for Trinidad and Tobago.


TT

An emoticon representing eyes that are crying


iki

(international standards) ISO 639-3 language code for Iko.


jee

(international standards) ISO 639-3 language code for Jerung.


etu

(international standards) ISO 639-3 language code for Ejagham.


isi

(international standards) ISO 639-3 language code for Nkem-Nkum.


(sciences) The plus-minus sign, indicating the tolerance or statistical margin of error of a quantity.

ax²+bx+c=0 rArr x=(-b plusmn √)/(2a).

(mathematics) Either value as a result of addition or subtraction.

(b) sporophyte with foot reduced, the entire sporophyte enveloped by the calyptra, which is ± stipitate at the base.

1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, Chicago, Ill.: Field Museum of Natural History, →ISBN, page 4:


YA

(metrology) Symbol for yottaampere, an SI unit of frequency equal to 10²⁴ amperes.


ADW

(international standards, aviation) IATA airport code for Andrews Air Force Base in Camp Springs, Maryland, United States.


sah

(international standards) ISO 639-2 & ISO 639-3 language code for Yakut.


SAW

(international standards, aviation) IATA airport code for Istanbul Sabiha Gökçen International Airport, which serves Istanbul, Turkey.


IAD

(international standards, aviation) IATA airport code for Washington Dulles International Airport, which serves Washington, D.C., United States.


DL

Specified in ISO 269 as an initialism of dimension lengthwise. Probably a backronym from German DIN lang, so named for the Deutsches Institut für Normung (German Institute for Standardisation Registered Association) and lang (“long”) (in reference to its shape).

(international standards) ISO 269 standard envelope size of 220 mm × 110 mm (8.66 in × 4.33 in), with a surface area of 242 cm² (37.5 sq in).


ori

(international standards) ISO 639-2 & ISO 639-3 language code for Odia.


POL

(international standards) ISO 3166-1 alpha-3 country code for Poland.


nog

(international standards) ISO 639-2 & ISO 639-3 language code for Nogai.


FOR

(international standards, aviation) IATA airport code for Fortaleza Airport, which serves Fortaleza, Ceará, Brazil.


hau

(international standards) ISO 639-2 & ISO 639-3 language code for Hausa.


AAR

(international standards, aviation) IATA airport code for Aarhus Airport, which serves Aarhus, Denmark.


elo

(international standards) ISO 639-3 language code for El Molo.


AND

(international standards) ISO 3166-1 alpha-3 country code for Andorra.


sh

(Serbo-Croatian): From Serbo-Croatian srpskohrvatski.

(international standards) ISO 639-1 language code for Serbo-Croatian.

Alternative form of sinh (“hyperbolic sine”)


bre

(international standards) ISO 639-2 & ISO 639-3 language code for Breton.


LV

(international standards) ISO 3166-1 alpha-2 country code for Latvia since 1992.


har

(international standards) ISO 639-3 language code for Harari.


kiu

(international standards) ISO 639-3 language code for Kirmanjki (Northern Zaza).


uz

abbrev

English <i class="Latn mention" lang="en">Uzbek</i>

(international standards) ISO 639-1 language code for Uzbek.


mun

(international standards) ISO 639-2 & ISO 639-5 language code for Munda languages.


PN

(metrology) Symbol for petanewton, an SI unit of force equal to 10¹⁵ newtons.


PN

Pitcairn Islands
Pitcairn Islands#English

(international standards) ISO 3166-1 alpha-2 country code for the Pitcairn Islands.


.cd

. + ISO 3166-1 country code for the Democratic Republic of the Congo, CD.

Democratic Republic of the Congo
Democratic Republic of the Congo

The Internet country code top-level domain (ccTLD) for the Democratic Republic of the Congo.


NGA

(international standards) ISO 3166-1 alpha-3 country code for Nigeria.


iu

(international standards) ISO 639-1 language code for Inuktitut.


There are two primary theories of the origin of the question mark. One is that ⟨?⟩ descends from the punctus interrogativus ⟨⹔⟩, which instructed the reader (or singer) to raise the pitch of their voice while coming to a stop.
Another theory is that it derives from overset Qo, an abbreviation of Latin quaestio (“question”), placed at the end of a question to mark it as such, and analogous to the derivation of ⟨!⟩.
There are no documented intermediary forms to support one theory over the other.

What is the next number in the sequence below?
1 4 9 16 25 36 ?

2009, Terry Stickels, Math Puzzles and Brainteasers, Grades 3-5: Over 300 Puzzles that Teach Math and Problem-Solving Skills (in English), John Wiley & Sons, →ISBN, page 6:

A placeholder for an unknown word, phrase, text, or numerical value.

(programming) A wildcard for one character in query language.

(programming) The ternary operator in some programming languages.

The string colou?r matches both "color" and "colour".

(regular expressions) Detects zero or one occurrences of the preceding element.

(networking) In a URL, begins a query string (a series of data formatted as field-value pairs).


cd

(metrology) Symbol for the candela, an SI unit of luminous intensity.


sed

(international standards) ISO 639-3 language code for Sedang.


tum

(international standards) ISO 639-2 & ISO 639-3 language code for Tumbuka.


mic

(international standards) ISO 639-2 & ISO 639-3 language code for Mi'kmaq.


GQ

Equatorial Guinea
Equatorial Guinea#English

(international standards) ISO 3166-1 alpha-2 country code for Equatorial Guinea.


aro

(international standards) ISO 639-3 language code for Araona.


Coordinate term: ∴


pli

(international standards) ISO 639-2 & ISO 639-3 language code for Pali.


ara

(international standards) ISO 639-2 & ISO 639-3 language code for Arabic.


ROL

(international standards, historical) ISO 4217 currency code for the former third Romanian leu; a currency used from 1952 to 2005.


ARM

(international standards) ISO 3166-1 alpha-3 country code for Armenia since 1992.


ARM

(international standards, historical) Unofficial non-ISO 4217 currency code for the former Argentine peso moneda nacional; a currency used from 1881 to 1970.


ug

(international standards) ISO 639-1 language code for Uyghur.

(typography) (metrology) Symbol for microgram, an SI unit of mass equal to 10⁻⁶ grams. Alternative form of µg


ron

(international standards) ISO 639-2/T & ISO 639-3 language code for Romanian.