spin

en-noun

spin (countable and uncountable, plural spins)

From Middle English spinnen, from Old English spinnan, from Proto-Germanic *spinnaną, from Proto-Indo-European *(s)penh₁-. Compare Low German spinnen, Dutch spinnen, German spinnen, Danish spinde, Swedish spinna.

(sports) Rotation of the ball as it flies through the air; sideways movement of the ball as it bounces.


torque

torque (countable and uncountable, plural torques)

→ Turkish: tork

Borrowed from Latin torqueō (“to twist”).

bor+

The relative strengths of the various torques will depend on both the spacecraft environment and the form and structure of the spacecraft itself.

1978, James Richard Wertz, Spacecraft Attitude Determination and Control, Springer, page 17:

The drillhead produces the drilling rotation and torque but also must slide out of position to allow the machine to manipulate the finisher drill steel and consumables.

2006, Department of Mining Engineering, Proceedings: 35th International Conference on Ground Control in Mining, volume 25, West Virginia University, page 162:

(physics, mechanics) A rotational or twisting effect of a force; a moment of force, defined for measurement purposes as an equivalent straight line force multiplied by the distance from the axis of rotation (SI unit newton metre or Nm; imperial unit pound-foot or lb·ft, not to be confused with the foot pound-force, commonly "foot-pound", a unit of work or energy)


turn

en-verb

turn (third-person singular simple present turns, present participle turning, simple past and past participle turned or (obsolete) turnt)

turns (present singular third-person)
turning (participle present)
turned (participle past)
turned (past)
turnt (obsolete participle past)
turnt (obsolete past)
turn (infinitive)

From Middle English turnen, from Old English turnian, tyrnan (“to turn, rotate, revolve”) and Old French torner (“to turn”), both from Latin tornāre (“to round off, turn in a lathe”), from tornus (“lathe”), from Ancient Greek τόρνος (tórnos, “turning-lathe: a tool used for making circles”), from Proto-Indo-European *terh₁- (“to rub, rub by turning, turn, twist, bore”). Cognate with Old English þrāwan (“to turn, twist, wind”), whence English throw. Displaced native Middle English wenden from Old English wendan (see wend), and Middle English trenden from Old English trendan (see trend), among several other terms.

lyödä kierre

in cricket, make the ball move sideways when it bounces

kiertää

of a cricket ball, move sideways when it bounces

-ul

e.g. “turn yellow”: sárga → sárgul, “turn brown”: barna → barnul

Turn the knob clockwise.

It was not far from the house; but the ground sank into a depression there, and the ridge of it behind shut out everything except just the roof of the tallest hayrick. As one sat on the sward behind the elm, with the back turned on the rick and nothing in front but the tall elms and the oaks in the other hedge, it was quite easy to fancy it the verge of the prairie with the backwoods close by.

1879, R[ichard] J[efferies], “The First Gun”, in The Amateur Poacher, London: Smith, Elder, & Co., […], →OCLC, pages 9–10:

Turbines have been around for a long time—windmills and water wheels are early examples. The name comes from the Latin turbo, meaning vortex, and thus the defining property of a turbine is that a fluid or gas turns the blades of a rotor, which is attached to a shaft that can perform useful work.

2013 July-August, Lee S. Langston, “The Adaptable Gas Turbine”, in American Scientist:

(transitive) To change the direction or orientation of, especially by rotation.


merry-go-round

Possibly from go round (= rotate) merrily.

Russell kept the merry-go-round moving with an RBI single that advanced Henderson to third.

(baseball, figurative) A series of singles and doubles that allow the batting team to score while still having runners on base who can be driven in by the next batter.


tumble

From Middle English tumblen (“to fall over and over again, tumble”), frequentative of Middle English tumben (“to fall, leap, dance”), from Old English tumbian, from Proto-Germanic *tūmōną (“to turn, rotate”). Cognate with Middle Dutch tumelen (whence Dutch tuimelen), Middle Low German tumelen, tummelen, German taumeln and Danish tumle.

der

When at last we stopped in a tumble of bodies on the grass, laughing, and in Dad's case, out of breath, we were like little kids (I mean 5 or 6! After all I am 12!) at the end of a playground session.

2008, David Joutras, A Ghost in the World, page 55:


tumble

en-verb

tumble (third-person singular simple present tumbles, present participle tumbling, simple past and past participle tumbled)

tumbles (present singular third-person)
tumbling (participle present)
tumbled (participle past)
tumbled (past)

He who tumbles from a tower surely has a greater blow than he who slides from a molehill.

1692–1717, Robert South, Twelve Sermons Preached upon Several Occasions, volume (please specify |volume=I to VI), London:

“Heavens!” exclaimed Nina, “the blue-stocking and the fogy!—and yours are pale blue, Eileen!—you’re about as self-conscious as Drina—slumping there with your hair tumbling à la Mérode! Oh, it's very picturesque, of course, but a straight spine and good grooming is better.[…]”

1907 August, Robert W[illiam] Chambers, The Younger Set, New York, N.Y.: D. Appleton & Company, →OCLC:

The two animals tumbled over each other in their eagerness to get inside, and heard the door shut behind them with great joy and relief.

1908, Kenneth Grahame, The Wind in the Willows:

Before so many of Europe's crowns came tumbling off the heads of their royal owners, Continental Europe could show a rich variety in the matter of royal trains.

1945 September and October, C. Hamilton Ellis, “Royal Trains—V”, in Railway Magazine, page 250:

(intransitive) To fall end over end; to roll over and over.

Now it’s easy to purchase bitcoins on any number of mainstream markets and “tumble” them so that their point of purchase is obscured.

2019, Brian Merchant, “Click Here to Kill: The dark world of online murder markets”, in Harper’s Magazine, volume 2020, number January:

(cryptocurrencies) To obscure the audit trail of funds by means of a tumbler.


roll

From Middle English rollen, partly from Old French roller, roler, röeler, röoler, from Medieval Latin rotulāre (“to roll; to revolve”), from Latin rotula (“a little wheel”), diminutive of rota (“a wheel”); partly from Anglo-Latin rollāre, from the same ultimate source.

der

Calculate the roll of that aircraft.

The rotation angle about the longitudinal axis.

kallistuminen

the rotation angle about the longitudinal axis


whirligig

/ˈwɜː.lɪ.ɡɪɡ/

/ˈwɝ.lɪ.ɡɪɡ/

From Middle English whirlegigge; equivalent to whirl (noun or verb) + gig (“a top”).

Why ſome are borne great, ſome atchieue greatneſſe, and ſome haue greatneſſe throwne vpon them. I was one ſir, in this Enterlude, one ſir Topas ſir, but that’s all one: By the Lo[r]d Foole, I am not mad: but do you remember, Madam, why laugh you at ſuch a barren raſcall, and you ſmile not he’s gag’d: and thus the whirlegigge of time, brings in his reuenges.

c. 1601–1602 (date written), William Shakespeare, “Twelfe Night, or What You Will”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act V, scene i], page 275, columns 1–2:

Anything that whirls or spins around, such as a toy top or a merry-go-round.

пумпал

anything that whirls or spins around, such as a toy


ambigram

From ambi- + -gram. Coined by Douglas Hofstadter in 1983-1984.

Two nonvisual factors provide dissymmetry and prevent the ambigram from existing in a static equilibrium; most of the letters in an ambigram metamorphose into other letters when reversed; and each of those accompanying sentences provides a different idea of the word's meaning.

1992, John Langdon, Wordplay, published 2005, page 52:

1997, Research and Education Networking, Volume 8, Issues 1-6, page 290,
An ambigram is a word that reads the same right-side-up and upside-down. MOW is a natural ambigram, for instance, but any word can be flipped if the right graphic artist gets his hands on it.

Next, I imagine that Switch #2 causes me every single weekend (and every other spare moment as well) to elect, instead of designing ambigrams or working hard on my book about being a strange loop, to spend hours on end watching professional football games on a huge-screen television and delightedly ogling all the busty babes in the beer ads.

2007, Douglas Hofstadter, I Am a Strange Loop, page 312:

A calligraphic design that may be read as the same word or phrase (or sometimes different words or phrases) when oriented in two different ways, usually when reflected along a vertical or horizontal axis or when rotated through 180 degrees.

Indiana University Bloomington
Merriam-Webster
ambigram

雙面語 /双面语

design that reads as the same word or phrase in two different orientations


gyrate

en-verb

gyrate (third-person singular simple present gyrates, present participle gyrating, simple past and past participle gyrated)

gyrates (present singular third-person)
gyrating (participle present)
gyrated (participle past)
gyrated (past)

/ˈd͡ʒaɪˌɹeɪt/

/d͡ʒaɪˈɹeɪt/

Back-formation from gyration, on the basis of -ate (verb-forming suffix), from gyre (“to spin around; to gyrate, to whirl; (rare) to make (something) spin or whirl around; to spin, to whirl”) + -ation (suffix indicating actions or processes), further from Late Middle English giren (“to turn (something) away; to cause (something) to revolve or rotate; to travel in a circle”), from Old French girer (“to turn”), from Latin gȳrō (“to turn in a circle, rotate; to circle or revolve around”), from gȳrus (“circle; circular motion; circuit, course”) + -ō (first conjugation verb-forming suffix), from Ancient Greek γῦρος (gûros, “a circle, a ring”), ultimately from Proto-Indo-European *gew- (“to bend; to curve”).

der

The stripper gyrated sexily around a pole.

(intransitive) To revolve round a central point; to move spirally about an axis, as a tornado.

въртя се

to revolve round a central point; to move spirally about an axis, as a tornado — see also revolve


gyrate

en-adj

gyrate (comparative more gyrate, superlative most gyrate)

more gyrate (comparative)
most gyrate (superlative)

From gyrus (“fold, convolution”) + -ate (adjective-forming suffix).


rotor

From an irregular shortening of rotator. Doublet of rota and ruote.

(aviation) The wing of a helicopter or other rotary-wing aircraft.


gyration

en-noun

gyration (countable and uncountable, plural gyrations)

/ˌd͡ʒaɪˈɹeɪʃ(ə)n/

From gyre (“to spin around; to gyrate, to whirl; (rare) to make (something) spin or whirl around; to spin, to whirl”) + -ation (suffix indicating actions or processes). Gyre is from Late Middle English giren (“to turn (something) away; to cause (something) to revolve or rotate; to travel in a circle”), from Old French girer (“to turn”), and directly from its etymon Latin gȳrāre, the present active infinitive of gȳrō (“to turn in a circle, rotate; to circle or revolve around”) (from gȳrus (“circle; circular motion; circuit, course”), from Ancient Greek γῦρος (gûros, “a circle, a ring”), from Proto-Indo-European *gew- (“to bend; to curve”)) + -ō (suffix forming regular first-conjugation verbs).

ĝirado

act of turning or whirling, especially around a fixed axis or centre — see also rotation

Novv that the ayre impelled returnes unto its place in a gyration or vvhirling, is evident from the Atomes or moates in the Sun. For vvhen the Sunne ſo enters a hole or vvindovv, that by its illumination the Atomes or moates become perceptible, if then by our breath the ayre bee gently impelled, it may be perceived that they vvill circularly returne, and in a gyration unto their places againe.

1646, Thomas Browne, “Of Bodies Electricall”, in Pseudodoxia Epidemica: […], London: […] T[homas] H[arper] for Edward Dod, […], →OCLC, 2nd book, page 80:

If Regularity and ſteddineſs accompany Velocity; the motion then leaves not the leaſt track in the ſenſitive. Thus a French Top, the common recreation of School-boys, throvvn from a cord vvhich vvas vvound about it, will ſtand as if it vvere fixt on the floor it lighted; and yet continue in its repeated Gyrations, vvhile the ſenſe diſcovers not the leaſt footſteps of that præcipitate Rotation.

1661, Joseph Glanvill, chapter IX, in The Vanity of Dogmatizing: Or Confidence in Opinions. […], London: […] E. C[otes] for Henry Eversden […], →OCLC, pages 80–81:

If a burning Coal be nimbly moved round in a Circle vvith Gyrations continually repeated, the vvhole Circle vvill appear like fire; the reaſon of vvhich is, that the ſenſation of the Coal in the ſeveral places of that Circle remains impreſt on the Senſorium, until the Coal return again to the ſame place.

1704, I[saac] N[ewton], “[The First Book of Opticks. Part II.] Prop[osition] V. Theo[ry] IV. [Exper[iment] X.]”, in Opticks: Or, A Treatise of the Reflexions, Refractions, Inflexions and Colours of Light. […], London: […] Sam[uel] Smith, and Benj[amin] Walford, printers to the Royal Society, […], →OCLC, page 104:

His life was a gyration of energetic curiosity; an insatiable whirl of social celebrity.

1847, B[enjamin] Disraeli, chapter XIV, in Tancred: Or, The New Crusade. […], volume I, London: Henry Colburn, […], →OCLC, book II, page 291:

If you question a seaman on the subject, whether mere coaster or circumnavigator, he will tell you that in a snow-storm, because of its constant eddyings and gyrations, frequent trimming of sails is more necessary than in any other gale, and that to steer a straight and steady course under such circumstances is for the time simply impossible.

1881 March, “Snow Storm Gales”, in Symon’s Monthly Meteorological Magazine, volume XVI, number CLXXXII, London: Edward Stanford, […], →OCLC, page 59:

[A] long table of ebony and ivory was unceremoniously cleared of the various objects of art which had been placed on it, and the roulette-wheel was enthroned there instead by the hands of Lady Kenilworth herself, and the little ball was set off on its momentous gyrations.

1897, Ouida [pseudonym; Maria Louise Ramé], chapter XIV, in The Massarenes, New York, N.Y.: R. F. Fenno & Company […]; London: Sampson Low, Marston & Co., →OCLC, page 182:

He followed Neena out among the dancers and she immediately started doing this sexy gyration right up on him. Guy got into the mood and they danced until he saw the waitress bringing their drinks over.

2003, Sheila Kinston Dean, chapter 16, in Full Circle, Boston, Mass.: Beatrice Joseph Publishing, →ISBN, page 186:

The gyration of the hips, quick hand movements, the expressive face and the energetic runs are newly discovered movement qualities that extend beyond their classical repertoire of codified meanings, leading Belle and Kethya [dancers] to become more expressive in their improvisations.

2016, How Ngean Lim, “Rhythmic Operations, Material Description, and Analysis in Dance”, in Thomas F. DeFrantz, Philipa Rothfield, editors, Choreography and Corporeality: Relay in Motion (New World Choreographies), London: Palgrave Macmillan, →DOI, →ISBN, page 108:

Cryptocurrency – digital money not backed by any nation – is famous for its wild and frequent gyrations.

2021 July 23, Eric Lipton, Ephrat Livni, “Crypto nomads: Surfing the world for risk and profit”, in The New York Times, New York, N.Y.: The New York Times Company, published 19 August 2021 (updated), →ISSN, →OCLC, archived from the original on 2022-03-10:

"Let's focus on the ones you can see, if your delicate sensibilities will allow it." Lillihammer leaned on the wall, next to a pair of figures frozen mid-gyration who bore, even in their chromatically-reduced state, a striking resemblance to Chelsea Smits and the late, unlamented Sergey Vanchev.

2022 October 7, HarryBlank, “A Clean Break”, in SCP Foundation, archived from the original on 2024-05-25:

(also figuratively) The act of turning or whirling, especially around a fixed axis or centre; a circular or spiral motion; rotation.

(specifically, Euclidean geometry) A rotation around an axis which is not the centre of rotational symmetry; an eccentric or off-centre rotation.


revolution

revolution (countable and uncountable, plural revolutions)

→ Japanese: レボリューション (reboryūshon)

From Middle English revolucion, borrowed from Old French revolucion, from Late Latin revolūtiōnem, accusative singular of revolūtiō (“the act of revolving; revolution”), from Latin revolvō (“roll back, revolve”).

The ratio between the speeds of revolution of wheel and disc is substantially equal to the reciprocal of the ratio between the diameter of the wheel and the diameter of the mean contact circle on the disc.

1912, P. M. Heldt, The Gasoline Automobile: Its Design and Construction, Volume II: Transmission, Running Gear and Control, The Horseless Age Co., published 1913, page 147:

The Earth has two motions: a daily revolution (or turning around) upon its axis, and a yearly course around the sun.

1864, D. M. Warren, The Common-School Geography, Revised edition, H. Cowperthwait & Co., page 6:

Numerous cases are recorded which incontestibly prove that during pregnancy, the uterus perform a half or even a complete revolution, on itself, producing torsion of the cervix […]

1878, George Fleming, A Text-Book of Veterinary Obstetrics, Baillière, Tindall, & Cox, page 123:

Rotation: the turning of an object around an axis, one complete turn of an object during rotation.


carousel

From French carrousel, from Italian carosello, from Sicilian caruseḍḍu and/or Neapolitan carusiello. Uncertain. Some suggested a derivation from carro (“cart”), from Latin carrus, but this does not fit the criteria of an appropriate morphological reconstruction. Not believed to be related to carousal.

graphical user interface
graphical user interface

(graphical user interface) A visual component that displays a horizontal series of items one at a time.


revolver

→ Catalan: revòlver

→ Chuvash: ляворвăр (ljavorvăr)

→ Crimean Tatar: revolver

→ Danish: revolver

→ Dutch: revolver

→ Esperanto: revolvero

→ Finnish: revolveri

→ French: revolver

→ Gagauz: livorver

→ Galician: revólver

→ German: Revolver

→ Hungarian: revolver

→ Italian: revolver

→ Japanese: リボルバー (riborubā)

Norwegian:

→ Norwegian Bokmål: revolver

→ Norwegian Nynorsk: revolver

→ Polish: rewolwer

→ Portuguese: revólver

→ Russian: револьвер (revolʹver)

Serbo-Croatian:

→ Cyrillic script: револвер

→ Latin script: revolver

→ Spanish: revólver

→ Swedish: revolver

→ Urum: levorver

→ Yiddish: רעוואָלווער (revolver)

From revolve + er, coined by American inventor Samuel Colt in 1835.

coin

(firearms) A handgun with a revolving chamber enabling several shots to be fired without reloading.

The debt is split between $6.5bn of term loans, as well as $6bn of senior and junior bonds and a $500mn revolver.

2023 December 16, “Musk told lenders they would not lose money on Twitter deal”, in FT Weekend, Companies & Markets, page 10:

(finance) Synonym of revolving line of credit, a form of credit permitting the holder to repeatedly borrow money.


whirl

en-verb

whirl (third-person singular simple present whirls, present participle whirling, simple past and past participle whirled)

whirls (present singular third-person)
whirling (participle present)
whirled (participle past)
whirled (past)

From Middle English whirlen, contracted from earlier *whirvelen, *whervelen, possibly from Old English *hwyrflian, *hweorflian (attested in hwirflung, hwerflung (“change, vicissitude”)), frequentative form of Old English hweorfan (“to turn”), itself from Proto-West Germanic *hwerban, from Proto-Germanic *hwerbaną (“to turn”); or perhaps from Old Norse hvirfla (“to go round, spin”). Cognate with Dutch wervelen (“to whirl, swirl”), German wirbeln (“to whirl, swirl”), Danish hvirvle (“to whirl”), Swedish virvla (older spelling hvirfla), Albanian vorbull (“a whirl”). Related to whirr and wharve.

without the wine–whine merger, non-rhotic

The dancer whirled across the stage, stopped, and whirled around to face the audience.

The house whirled around two or three times and rose slowly through the air. Dorothy felt as if she were going up in a balloon.

1900 May 17, L[yman] Frank Baum, The Wonderful Wizard of Oz, Chicago, Ill.; New York, N.Y.: Geo[rge] M[elvin] Hill Co., →OCLC:

(intransitive) To rotate, revolve, spin or turn rapidly.


rotate

rotate (third-person singular simple present rotates, present participle rotating, simple past and past participle rotated)

rotates (present singular third-person)
rotating (participle present)
rotated (participle past)
rotated (past)
rotate (infinitive)

→ Finnish: rotatoida

Borrowed from Latin rotātus, perfect passive participle of rotō (“revolve”), from rota (“wheel”).

He rotated in his chair to face me.

The earth rotates.

(intransitive) To spin, turn, or revolve.

The aircraft rotates at sixty knots.

(intransitive, of aircraft) To lift the nose during takeoff, just prior to liftoff.

въртя

to change which tire is on each corner of the car, so that they wear evenly

Rotate the dial to the left.

(transitive) To spin, turn, or revolve something.

I've always admired the Japanese point of view that holds it best not to have a great number of objects around at one time but to rotate possessions — and display them with great simplicity.

1975, “Architectural Digest”, in (Please provide the book title or journal name), volume 32, page 112:

(transitive) To advance something through a sequence; to allocate or deploy in turns.


revolve

From Middle English revolven (“to change direction”), borrowed from Old French revolver (“to reflect upon”), from Latin revolvere (“turn over, roll back, reflect upon”), from re- (“back”) + volvō (“roll”); see voluble, volve.

der

(theater) The rotation of part of the scenery within a theatrical production.


torsion

en-noun

torsion (countable and uncountable, plural torsions)

From Middle English torcion, from Middle French torsion, from Late Latin torsiōnem, from Latin tortiō, from torqueō (“twist, turn”). See torture, -tort.

The act of turning or twisting, or the state of being twisted; the twisting or wrenching of a body by the exertion of a lateral force tending to turn one end or part of it about a longitudinal axis, while the other is held fast or turned in the opposite direction.


angular velocity

angular velocity (countable and uncountable, plural angular velocities)

1963, Richard Feynman, The Feynman Lectures on Physics (1963) Ch. 18 Rotation in Two Dimensions, 18–2 Rotation of a rigid body.
First, we have the angle θ which defines how far the body has gone around; this replaces the distance s, which defines how far it has gone along. In the same manner, we have a velocity of turning, ω=dθ/dt, which tells us how much the angle changes in a second, just as v=ds/dt describes how fast a thing moves, or how far it moves in a second. If the angle is measured in radians, then the angular velocity ω will be so and so many radians per second. The greater the angular velocity, the faster the object is turning, the faster the angle changes.

Wikipedia: Differential
A differential is a device, usually, but not necessarily, employing gears, which is connected to the outside world by three shafts, through which it transmits torque and rotation. The gears or other components make the three shafts rotate in such a way that a=pb+qc, where a, b, and c are the angular velocities of the three shafts, and p and q are constants. … In automobiles and other wheeled vehicles, a differential allows the driving road wheels to rotate at different speeds. This is necessary when the vehicle turns, making the wheel that is traveling around the outside of the turning curve roll farther and faster than the other. The engine is connected to the shaft rotating at angular velocity a. The driving wheels are connected to the other two shafts, and p and q are equal.ᵂᴾ

(mathematics, physics) The angle turned, per unit time, by a body rotating about an axis; the rate of rotation through an angle.


angular acceleration

angular acceleration (usually uncountable, plural angular accelerations)

(classical mechanics) The rate of change of angular velocity, often represented by α.


pulsar

LL-Q1860 (eng)-Flame, not lame-pulsar.wav

Blend of pulsating + (radio) star, patterned after quasar. Coined by British astronomers Antony Hewish and Jocelyn Bell in 1968, and first used in print in The Daily Telegraph. Analyzable as pulse + -ar

coin

(astronomy) A rotating neutron star that emits radio pulses periodically.

Antony Hewish
Jocelyn Bell Burnell
The Daily Telegraph
en:pulsar


spinning top

Patel says the muons behave a bit like a child’s spinning top, in rotating around the axis of the magnetic field. However, as the muons move, they wobble.

2023 August 11, Nicola Davis, “Scientists may be on brink of discovering fifth force of nature”, in The Guardian:

A toy with a tapering point that can be made to spin on its axis, either with a built-in pump-action handle, with the fingers or with a string.


rotator

(Internet) A banner ad that cycles through multiple advertisements.


moment of inertia

en-noun

moment of inertia (plural moments of inertia)

The moment of inertia of a rigid body is a quantity that determines the torque needed for a given angular acceleration about a given rotational axis, analogous to how mass determines the force needed for a given acceleration.

The moments of inertia of a heterogeneous body whose boundary is a surface of uniform density may sometimes be found by the method of differentiation.

1882, Edward John Routh, The Elementary Part of a Treatise on the Dynamics of a System of Rigid Bodies, 4th edition, MacMillan & Co., page 10:

Consequently, the moment of inertia of a body relative to any axis can be found when that for the parallel axis through its centre of gravity is known.

1884, Benjamin Williamson, An Elementary Treatise on the Integral Calculus, 4th edition, Appleton and Company, page 292:

(physics, classical mechanics) A measure of a rigid body's resistance to change in its angular velocity around a given axis.

moment setrvačnosti

measure of resistance to change in angular velocity

Stresses due to vertical shearing forces also depend on moment of inertia and are discussed in Chapter 8.
Some mathematicians and stress analysts use the term second moment of area instead of moment of inertia. That term is, in fact, more descriptive of the definition of this property in the following discussion.

2007, Robert L. Mott, Applied Strength of Materials, 5th edition, Taylor & Francis (CRC Press), page 323:

Second moment of area
second moment of area

(engineering, structural engineering) Second moment of area; a measure of a rigid body's resistance to bending.


centrifuge

From French centrifuge, from Latin centrum (“center”) + fugiō (“to flee”). Equivalent to centri- + -fuge.

A device in which a mixture of denser and lighter materials (normally dispersed in a liquid) is separated by being spun about a central axis at high speed.

(figuratively) An apparatus in which humans are spun to simulate acceleration in an aircraft or spacecraft.

By extension, any device which rotates in order to produce artificial gravity (in the form of centrifugal force)


centrifuge

en-verb

centrifuge (third-person singular simple present centrifuges, present participle centrifuging, simple past and past participle centrifuged)

centrifuges (present singular third-person)
centrifuging (participle present)
centrifuged (participle past)
centrifuged (past)

To rotate something in a centrifuge, typically in order to separate its constituents.

使離心 /使离心

to rotate something in a centrifuge in order to separate its constituents


irrotational

LL-Q1860 (eng)-Flame, not lame-irrotational.wav

Not rotating or not pertaining to rotation.


ultracentrifuge

A high-speed centrifuge, especially one free from convection that is used to separate colloidal particles.


Russian roulette

From roulette, a game of chance involving a revolving wheel. The first description is apparently in "The Fatalist," an 1840 short story by Russian writer Mikhail Lermontov.

(idiomatic, games) A deadly game in which a person loads a single bullet in the cylinder of a revolver, spins the cylinder so that the bullet's location is unknown, points the muzzle at his/her head, and pulls the trigger. In its most lethal form, played by multiple participants each of whom takes a turn until the weapon discharges.

رُولِيت رُوسِيّ

deadly game with revolver and random spinning


Karussell

de-noun

Karussell n (strong, genitive Karusselles or Karussells, plural Karusselle or Karussells)

Karusselles (genitive)
Karussells (genitive)
Karusselle (plural)
Karussells (plural)
Karussell (nominative singular)
Karusselle (definite nominative plural)
Karussells (definite nominative plural)
Karusselles (genitive singular)
Karussells (genitive singular)
Karusselle (definite genitive plural)
Karussells (definite genitive plural)
Karussell (dative singular)
Karusselle (dative singular)
Karussellen (dative definite plural)
Karussells (dative definite plural)
Karussell (accusative singular)
Karusselle (accusative definite plural)
Karussells (accusative definite plural)

(Amusement ride) carousel (US), merry-go-round (UK)


angular momentum

en-noun

angular momentum (plural angular momenta)

(physics) The vector product that describes the rotary inertia of a system about an axis and is conserved in a closed system. For an isolated rigid body, it is a measure of the extent to which an object will continue to rotate in the absence of an applied torque.


moment of force

moment of force (plural moments of force)

(physics) The turning effect of a force applied to a rotational system at a distance from the axis of rotation. The moment is equal to the magnitude of the force multiplied by the perpendicular distance between its line of action and the axis of rotation.


revolving door

A door that rotates around a central pivot.

Indeed, we happily condemn damaged children – at enormous expense – to hellholes like Feltham, where they are more likely to be assaulted or killed than to find an escape from the revolving doors of courts, prisons and addiction.

2020 July 23, Chris Daw, “'A stain on national life': why are we locking up so many children?'”, in The Guardian:

After the prime minister’s abrupt Downing Street statement, in which she announced that another leadership contest would be held within a week, Starmer attacked what he called “this revolving door of chaos”.

2022 October 20, Heather Stewart, quoting Keir Starmer, “Keir Starmer renews call for immediate general election after Truss resigns”, in The Guardian:

(figuratively) A system or institution that people exit and immediately reenter.

We've had 14 Secretaries of State through the revolving door in the first 23 years of this century. And the civil servants rotate through the departments with similar speed.

2023 June 28, Anthony Smith talks to Paul Clifton, “The industry has to go back to basics”, in RAIL, number 986, page 40:

(politics) A movement of personnel between roles as legislators and regulators, on the one hand, and members of the industries affected by the legislation and regulation, on the other.


spinner

From Middle English spynnere; equivalent to spin + -er.

2021, Neha Bedi, Sachin Bajaj, The Sardar of Spin
I can ascertain that even in the present era where T20 cricket has redefined spin bowling and spinners have started bowling doosras and teesras and fire the deliveries in, you can expect Bishan Singh Bedi to stick to his original definition, and insist that, 'A spinner is one who turns the ball...'


пулсар

bg-noun

пулса́р • (pulsár) m

пулса́р (canonical)
pulsár (romanization)
пулса́р (indefinite singular)
пулса́ри (indefinite plural)
пулса́рът (definite singular subjective)
пулса́рите (definite plural subjective)
пулса́ра (definite objective singular)
пулса́рите (definite objective plural)
пулса́ра (count-form plural)

bg-ndecl

пулса́р<(-ь)>


autorotation

en-noun

autorotation (countable and uncountable, plural autorotations)

(aviation) The rotation of the blades of a helicopter driven solely by the action of ascending air

autorotazione

rotation of the blades of a helicopter by ascending air


spin up

en-verb

spin up (third-person singular simple present spins up, present participle spinning up, simple past and past participle spun up)

spins up (present singular third-person)
spinning up (participle present)
spun up (participle past)
spun up (past)

The auditorium opens and the seats fill. As ever, there's a brief, grey dead time while Wheeler waits for all the machinery of the performance to spin up. The anxious feeling is stronger than usual today. It grips him, an uncharacteristic urge to run away. Sure, he thinks. I could just junk my career, right now. Pack it in and make for the stage door. Maybe the taxi'll still be there.

2019 April 10, qntm, “CASE HATE RED”, in SCP Foundation, archived from the original on 2024-05-29:

(figurative, intransitive) To be brought into full operation; to reach full potential or capacity; to spool up.


spin down

spin down (third-person singular simple present spins down, present participle spinning down, simple past and past participle spun down)

spins down (present singular third-person)
spinning down (participle present)
spun down (participle past)
spun down (past)

(of a rotating body) To reduce its speed of rotation.


symmetry group

[The] situation is more delicate in the case of higher dimensional symmetry groups; it is not in general possible to reduce the order of an equation invariant under an r-parameter symmetry group by r using only quadratures.

1993, Peter J. Olver, Applications of Lie Groups to Differential Equations, published 2000, page 76:

It is often assumed that the design unit inside each fundamental region (particularly for monotranslational symmetry groups p111 and p1a1 and ditranslational symmetry groups p1 and pg) is asymmetric.

2000, C. E. Horne, Geometric Symmetry in Patterns and Tilings, page 79:

The structure of the symmetry group of a molecule affects several spectroscopic aspects and vice versa. Thus, it is clearly important to know the possible symmetries of fullerenes and similar structures.
In this chapter, we study symmetry groups of fulleroids.

2010, Stanislav Jendrol, František Kardoš, “28: Symmetry of Fulleroids”, in Klaus D. Sattler, editor, Handbook of Nanophysics: Clusters and Fullerenes, pages 28–1:

(geometry, algebra, group theory) A group whose elements are all the transformations under which a given object remains invariant and whose group operation is function composition.

full symmetry group

emphasises the inclusion of orientation-reversing transformations


თისკუპანი

head

თისკუპანი • (tisǩup̌ani) (Latin spelling tişǩup̌ani)

tisǩup̌ani (romanization)
tişǩup̌ani (romanization)

From თიშ (tiş, “head's”) + *კუპანი (*ǩup̌ani, unknown). Probably evolved form a sense of upside down. Compare Laz თიკოპალი (tiǩop̌ali, “upside-down”).

af

ბერე ბორტიში თიშკუპანიში ოსთერუ დიდო კაი მიწონტუ

When I was a kid, I used to love to do somersaults

bere borťişi tişǩup̌anişi osteru dido ǩai miǯonťu


пумпал

bg-noun

пу́мпал • (púmpal) m (diminutive пу́мпалче)

пу́мпал (canonical)
púmpal (romanization)
пу́мпалче (diminutive)
пу́мпал (indefinite singular)
пу́мпали (indefinite plural)
пу́мпалът (definite singular subjective)
пу́мпалите (definite plural subjective)
пу́мпала (definite objective singular)
пу́мпалите (definite objective plural)
пу́мпала (count-form plural)

spinning top (usually as a children's toy)

(figurative) a person who doesn't sit still; who is quick to get things done


centripetal acceleration

en-noun

centripetal acceleration (plural centripetal accelerations)

(physics) acceleration due to centripetal force.