gwerθ

Old Breton: uuert

Middle Breton: guerz

Breton: gwerzh

Cornish: gwerth

Middle Welsh: gwerth

Welsh: gwerth

Possibly from Proto-Celtic *wertom, from Proto-Indo-European *wért-o-m, for Proto-Indo-European *wert- (“to turn”), or perhaps borrowed from Germanic, ultimately from Proto-Germanic *werþą (“worth, value”) of the same root.


gwehantuɨn

Old Cornish: guaintoin

desc

Cornish: gwenton, gwaynten (Standard Cornish)

Old Welsh: guiannuin

Middle Welsh: gwaeanhwyn

Welsh: gwanwyn

From *gwehant + *-uɨn, from Proto-Celtic *wesants (perhaps whence Gaulish simivis (“august”, literally “half-spring”)), from Proto-Indo-European *wésn-ont-s ~ *usn̥-n̥t-és (whence Sanskrit वसन्त (vasantá)), from *wós-r̥ ~ *wés-n̥s (“spring (season)”) + *-onts ~ *-n̥tés.


kuml

Breton: koumoul

Cornish: kommol

Middle Welsh: cwmwl

Welsh: cwmwl

Borrowed from Latin cumulus. The lack of lenition on the m is problematic; one would have expected *kuβ̃(u)l. GPC suggests that, like French comble, it comes from a Vulgar Latin *cumblus from *cumlus, syncopated from cumulus, and not directly from cumulus itself.


kėres

Middle Breton: queres

Breton: kerez

Cornish: keres

Welsh: ceirios

Borrowed from Late Latin ceresia, perhaps through Proto-Celtic *keresyā, from Latin cerasium.


kėfɨl

Old Breton: cefel

Breton: kefel

Old Welsh: cefel, chefel

Middle Welsh: keffyl

Welsh: ceffyl

From Proto-Celtic *kappilos, a variant form of *kaballos.


nėdr

Old Breton: natrolion pl

Middle Breton: nazr, aezr

Breton: nàer

Old Cornish: nader

Cornish: nader

Welsh: neidr

From Proto-Celtic *natrī, from Proto-Indo-European *(s)n̥H-tr-íh₂, from *(s)néHtr̥.


hembrüngɨd

Middle Breton: hambrouc

Breton: ambroug

Cornish: hembronk

Middle Welsh: hebrwng

Welsh: hebrwng

From *hem- + *brüngɨd, presumably from Proto-Celtic *brunketi, perhaps from Proto-Indo-European *br-n̥k-e-ti, from *bʰer- (“to bear, carry”) + *h₂neḱ- (“to reach, bring”), probably through a stage where the latter two roots were concatenated into one (compare Proto-Germanic *bringaną (“to bring”)).


Ἀργεντοκόξος

From Proto-Celtic *argantom (“silver”) + *koxsā (“leg”); corresponding to late *arɣant + *koɨs. Cited in a Koine Greek text by Dio Chrysostom.


gwüxī

Old Breton: guohi

Middle Breton: goui

Breton: moui, boui

Old Cornish: guhi-en

Cornish: goghi, gohi

Middle Welsh: gwychi

Welsh: gwchi

→ Old Irish: foich ()
Middle Irish: foich
Irish: foiche (“wasp”)

From Proto-Celtic *woxsī, perhaps generalized from the plural, from Proto-Indo-European *wóps-ih₂, from *wóps.


llaɨθ

Old Breton: laed

Middle Breton: laez

Breton: laezh

Old Cornish: lait

Middle Cornish: leth, leyth

Cornish: leth

Middle Welsh: llaeth

Welsh: llaeth

Uncertain; from earlier *llaɣθ, possibly either borrowed from Latin lacte, lac (“milk”), or inherited from Proto-Celtic *laxtos. Parallel borrowing or cognate with Old Irish lacht (“milk”).


kọs

Old Breton: cos

Middle Breton: queux

Breton: keuz

desctree

Old Cornish: cos
Middle Cornish: kez, keas
Cornish: keus

Old Welsh: caus

Middle Welsh: caws

Welsh: caws

Borrowed from Latin cāseus. Parallel borrowing with Old Irish cáise (“cheese”).


aβʉ

Middle Breton: auu

Breton: avu

Old Cornish: avi

Cornish: avi

Middle Welsh: auu

Welsh: afu

From Proto-Celtic *awV-. Cognate with Middle Irish áe.


kögin

Old Breton: covin

Breton: kegin

Old Cornish: keghin

Middle Cornish: cegin

Cornish: kegin

Middle Welsh: kegyn

Welsh: cegin

Borrowed from Late Latin cocīna (“kitchen”). Parallel borrowing to Old Irish cucann (“kitchen”).


llin

Middle Breton: lin

Cornish: lin

Welsh: llin

From Proto-Celtic *līnom. Cognate with Old Irish lín (“linen”).


llin

Middle Breton: lin

Cornish: lin

Middle Welsh: llin

From Proto-Celtic *līnom. Cognate with Old Irish lín (“full number”).


pɨsk

Middle Breton: pesq

Breton: pesk

Old Cornish: pisc

Middle Cornish: pysk

desc

Cornish: pysk, pesk (Revived Late Cornish)

Middle Welsh: pysc

q

Welsh: pysg (obsolete, displaced by the derived term pysgodyn)

Borrowed from Latin piscis. Displaced the native cognate *uɨsk (which survives only in the hydronym *Uɨsk), from Proto-Celtic *ɸeiskos (“fish”). Cognate with the inherited Old Irish íasc (“fish”).


egluɨs

Middle Breton: ylis (influenced by (Old) French eglise)

Breton: iliz

Old Cornish: eglos

Middle Cornish: eglos, egles, eglus

Cornish: eglos

Old Welsh: eccluys

Middle Welsh: eglwys, egluys

Welsh: eglwys

→ English: Eccles

Borrowed from Vulgar Latin eclēsia, from Latin ecclēsia. Parallel borrowing with Old Irish eclais (“church”).


niβ̃er

Old Breton: nimer

Middle Breton: niuer

Breton: niver

Middle Cornish: nyver, never, niver

Cornish: niver

Old Welsh: nimer

Middle Welsh: niuer, yniuer, eniuer

Welsh: nifer

Borrowed from Latin numerus. The development of the first vowel to *i is unique and has not been explained with certainty. Parallel borrowing with Old Irish nuimir (“number”).


gwoɨθ

Middle Breton: goaz

Breton: gwazh

Cornish: gweth

Middle Welsh: gwaeth

Welsh: gwaeth

Uncertain; possibly a back-formation from *gwoɨθhaβ̃. Alternatively cognate with with Middle Irish facht (“malice?”).

comparative degree of *gwoɨl (“bad”): worse


llaɣhaβ̃

Old Breton: leham, leiham, laham

Cornish: lyha

Middle Welsh: lleiaf

Welsh: lleiaf, lleia (colloquial)

From Proto-Celtic *lagisamos. Equivalent to *llaɣw (“small”) + *-haβ̃ (superlative suffix).

af

superlative degree of *llaɣw (“small”): smallest, least


llaɣw

head

*llaɣw (comparative *llaɣü, superlative *llaɣhaβ̃)

llaɣü (comparative)
llaɣhaβ̃ (superlative)

Old Breton: lau

Middle Breton: lau

Breton: law

Middle Welsh: llaw


gwoɨl

*gwoɨl (comparative *gwoɨθ, superlative *gwoɨθhaβ̃)

gwoɨθ (comparative)
gwoɨθhaβ̃ (superlative)

Breton: goal, gwal, gail

Welsh: gwael

Possibly from Proto-Celtic *uɸoɸedlos, from Proto-Indo-European *(s)upu-ped-ló-s, from *(s)up- + *ped- (“to walk, fall, stumble”) + *-lós.


-ɨnn

Middle Welsh: -yn

Welsh: -yn

From Proto-Celtic *-inyos. Cognate with Old Irish -(i)ne.

tanaw (“thin”) + *-ɨnn → *tenewɨnn (“side, flank”)

Forms abstract derivatives of certain nouns and adjectives.

grọn (“grain”) + *-ɨnn → *grọnɨnn (“a grain”)


porxell

Old Breton: porchill

Middle Breton: porchell

Breton: porc'hell

Old Cornish: porchel

Middle Cornish: porchel, porhel

Cornish: porghel, porhel

Middle Welsh: porchell

Welsh: porchell

Borrowed from Late Latin porcellus. Cognate with Proto-Celtic *ɸorkos (“pork, piglet”), both from Proto-Indo-European *pórḱos (“pig”).


estrọn

Borrowed from Vulgar Latin *estrāneus, from Latin extrāneus.


estrọn

Middle Breton: estren

Breton: estren

Middle Cornish: estren

Cornish: estren

Middle Welsh: estrawn

Welsh: estron


Düβnėnt

Middle Breton:

Breton: Devnent

Middle Cornish: Dewnans

Cornish: Dewnens, Dewnans

Middle Welsh: Dyfneint

Welsh: Dyfnaint

→? Old English: Defena (or from a reflex of *Dubnonī?)

Middle English: Devene

English: Devon

⇒ Old English: Defenascir

Middle English: Devenescire

English: Devonshire

From an earlier *Dub(no)nantī, a compound equivalent to *duβn ("deep") + *nant ("valley"). The i-affection may originate from a plural or genitive case ending.
Although sometimes held to be directly from Proto-Celtic *Dubnonī (whence Latin Dumnōniī), this cannot fully explain the final *-t.

Devon, the main territory of the historic Dumnonian kingdom and a later county of England.


hux

Old Breton: hoch

Middle Breton: hoc’h, houc’h

Breton: soc’h

Old Cornish: hoch

Cornish: hogh

Welsh: hwch

→? Old English: hogg (“hog”) (see there for further descendants)

From Proto-Celtic *sukkos. Doublet of *sux (“plowshare”).


Körnɨw

Middle Breton: Querne, Querneau

Breton: Kerne, Kernev

Middle Cornish: Kernow

Cornish: Kernow

Middle Welsh: Kernyw

Welsh: Cernyw

→⇒ Old English: Cornwealas

Middle English: Cornwaile

English: Cornwall

→ Old French: Cornouaille

French: Cornouaille

→ Medieval Latin: Cornubia

Consistent with derivation from Proto-Celtic *Kornowī with final and internal i-affection, i.e. *Kornowī > *Kornɨwī > *Körnɨw. This would imply an earlier place name *Kornowī (“people of the horn”), which can possibly be inferred from the Ravenna Cosmography; see Cornovii, Cornovii (Cornwall), ultimately from Proto-Indo-European *ḱerh₂- (“horn”).
A fossilized genitive of this form may be found in Middle Welsh Corneu < *Kornowyās.

Cornwall, a territory of the Dumnonian kingdom and subsequently a county of England.

Cornouaille, a historical region of Brittany.


funtọn

Old Breton: funtun, funton

Middle Breton: feunten, feunteun

Breton: feunteun

Old Cornish: funten

Middle Cornish: fenton, fenten, fynten

Cornish: fenten

Old Welsh: finnaun, fynnaun (nn < nt by assimilation)

Middle Welsh: fynnawn, fynhawn

Welsh: ffynnon

Borrowed from Late Latin fontāna, with regular raising of *o to *u before a nasal and stop. Compare Old English *funta, recorded in toponyms across Southern England, which in light of the vowel quality may be an early borrowing from Brythonic.


kėw

Middle Breton: queu

Breton: kev

Middle Cornish: *kew (see notes)

Middle Welsh: keu

Welsh: cau

From Proto-Celtic *kawyos, perhaps from Proto-Indo-European *ḱh₁u-yó-s, from *ḱewh₁- (“to swell”). Cognate with Old Irish cuae, cue (“hollow”) (whence Irish cuas), Latin cavus. Doublet of *koudọd, borrowed from Latin cavitātem.


kėfɨlọg

Middle Breton: queffelec

Breton: kefeleg

Middle Cornish: kyvelak

Cornish: kevelek

Middle Welsh: cyffylog

Welsh: cyffylog

Perhaps from *kėfɨl (“horse”) + *-ọg, named for the similarity between the bird's call and the snort of a horse.


Kʉstentin

Old Breton: Custentin

Breton: Kustentin

Old Cornish: Custentin

Old Welsh: Custenhin, Custennhin

desc

Middle Welsh: Custenin, Custennin, Custenhin

Welsh: Cystennin

Borrowed from Vulgar Latin Cōstantīnus, from Latin Cōnstantīnus.

a male given name from Latin, equivalent to English Constantine


fruɨθ

Middle Breton: froez, frouez

Breton: frouezh pl

Old Cornish: fruit

→ Cornish: frooth pl (semi-learned)

Middle Welsh: ffrwyth

Welsh: ffrwyth

From earlier *fruxtos, borrowed Latin frūctus.


merθɨr

Middle Breton: merzer

Breton: merzher

Middle Cornish: *merthur (in compound)

Cornish: merther

Middle Welsh: merthyr

Welsh: merthyr

Borrowed from Latin martyr. This cannot regularly reflect an underlying, pre-apocope *martɨr (otherwise **merθr would be expected), so it is likely that the form acquired a Brythonic case ending prior to apocope (compare crux > *cruxsā > *kroɨs). Cognate with Old Irish martar. The second sense may be an independent borrowing from Ecclesiastical Latin martyrium.

(in toponyms) martyrium; burial place of a martyr


pɨskọd

Middle Breton: pesquet

Breton: pesked

Middle Cornish: puskes

Cornish: puskes, pùscas

Middle Welsh: pysgawd

Welsh: pysgod

Borrowed from Latin piscātus.
The classical usage of piscātus primarily verbal refers to the act of fishing, but as a verbal noun it developed the sense "catch, caught fish" in a collective sense. This is evidently the meaning that was carried into Proto-Brythonic, where it may have further developed a sense of "fish used as food" continued in Welsh (compare Spanish pescado for a parallel development). This plural would then have taken a regular singulative form *pɨskọdɨnn.
Subsequently, *pɨskọd was generalized as the plural of *pɨsk (“fish”) due to the appropriate grammatical number and semantics of the two terms. As a corollary, this resulted in two competing singular terms for "fish", *pɨsk and *pɨskodɨnn; the former was generalized in Breton and Cornish, while the latter became the general form in Welsh.

(possibly) food fish, fish meat used as food


traɨθ

Middle Breton: traez

Breton: traezh

Old Cornish: trait

Middle Cornish: traith, treath

Cornish: treth

Middle Welsh: traeth

Welsh: traeth

Although often supposed to be a borrowing from Latin tractus (“stretch, tract of land”) this poses semantic difficulties, and moreover the presence of an exact parallel in Old Irish tracht (“beach”) suggests instead descent from Proto-Celtic *traxtus, which could itself be from the same source as tractus (Proto-Indo-European *dʰregʰ- (“to draw out, pull”)).


haluɨn

Middle Breton: halon

Breton: halen

Old Cornish: haloin

Middle Cornish: halan, halen

Middle Welsh: halwyn, halaen, halen

Welsh: halen

From Proto-Celtic *saleinos, from Proto-Indo-European *séh₂ls (“salt”). Doublet of *heli (“brine”) and *selsig (“sausages”).


Llow

Old Welsh: Lou

Middle Welsh: Lleu

Lleu, a pre-Christian deity continued as a mythological hero. See Lleu Llaw Gyffes.


gwɨrð

Middle Breton: *guerz

Breton: gwerzh (dialectal)

q

⇒ Middle Breton: guezr (with metathesis, influenced by guezr (“glass”))

Breton: gwer

Old Cornish: guirt

Middle Cornish: gwirdh

Cornish: gwyrdh

>? Middle Cornish: gwer

Cornish: gwer

Old Welsh: guird

Middle Welsh: gwyrð

Welsh: gwyrdd

Borrowed from Vulgar Latin virdis (attested in the Appendix Probi), from Latin viridis via syncope.


kuwann

Old Breton: couann, couhann

Middle Breton: couhenn, caouënn

Breton: kaouenn
→ Cornish: cowan

Early Vannetais Breton: cohan [1732 CE]

Vannetais Breton: kohann

Middle Welsh: cuan

From Proto-Celtic *kuwannos.
The descendants reflect dissimilation of pretonic *-uw- in differing ways. In West Brythonic this was fronted to *-ʉw-, giving Middle Welsh -u-, while in Southwest Brythonic this was lowered to *-ọw-. The latter has merged with the reflexes of Proto-Brythonic *-ow- in most dialects of Breton, but a distinction is maintained in Vannetais.


llowen

Old Breton: louuen

Middle Breton: louen

Breton: laouen

Old Cornish: louen

Middle Cornish: lowen

Cornish: lowen

Middle Welsh: llawen

Welsh: llawen

From Proto-Celtic *lowenos, from Proto-Indo-European *leh₂w- (“gain, benefit”).


porθ

Middle Breton: porz

Breton: porzh

Old Cornish: porth

Middle Cornish: porth

Cornish: porth

Old Welsh: porth

Middle Welsh: porth

Welsh: porth (“portal”)


porθ

Middle Breton: porz

Breton: porzh

Middle Cornish: porth

Cornish: porth

Old Welsh: porth

Middle Welsh: porth

Welsh: porth (“port”)

Borrowed from Latin portus. Doublet of *rrɨd and *forð. Parallel borrowing with Old Irish port (“place, shore”).


pexọd

Middle Breton: pechet

Breton: pec’hed

Middle Cornish: peghes

⇒ Middle Cornish: pegh

Cornish: pegh

Middle Welsh: pechawt

Welsh: pechod

Borrowed from Latin peccātum. Parallel borrowing with Old Irish peccad (“sin”).


gwɨdr

Middle Breton: guezr

Breton: gwer

Middle Cornish: gweder

Cornish: gweder

Middle Welsh: gwydyr

Welsh: gwydr

Borrowed from Latin vitrum. Likely parallel borrowing with Irish fuither (“glass”).


ɨntr

Old Breton: entr-

Middle Breton: entre, intre

Breton: etre

Middle Cornish: yntre, ynter

Cornish: yntra, ynter

Old Welsh: ithr

Welsh: ythr

From Proto-Celtic *enter, from Proto-Indo-European *h₁entér.
The development of */ntr/ to /θr/ in Old Welsh is regular.


tėrðɨd

Old Breton: tardom

Middle Breton: tarza

Middle Cornish: tardha

Middle Welsh: tarddu

Presumably from Proto-Celtic *taryeti, possibly from Proto-Indo-European *tr̥h₂-yé-ti, from *terh₂- (“to cross over, pass through, overcome”).


saɣeθ

Middle Breton: saez

Breton: saezh

Middle Cornish: seth

Cornish: seth

Middle Welsh: saeth

Welsh: saeth

Borrowed from Latin sagitta. Parallel borrowing with Old Irish saiget.


dọβ̃

Middle Breton: deuff

Breton: deuñv

Old Cornish: dof

Middle Cornish: def, duf

Old Welsh: dauu, daum
Middle Welsh: daw

From Proto-Celtic *dāmos, from Proto-Indo-European *dōm-o-s (“belonging to the house”), a vṛddhi derivative of Proto-Indo-European *dom-o-s, thematized form of *dṓm (“house, home”).
The meaning of "client" is attested only in Old Welsh, but this sense is likely to be inherited based on the Old Irish cognate dám (“company, retinue”).


plʉβ̃

head

*plʉβ̃ m pl or f pl (singulative *plʉβ̃ɨnn, *plʉβ̃enn)

plʉβ̃ɨnn (singulative)
plʉβ̃enn (singulative)

Old Breton: *plum

Middle Breton: pluff

Breton: pluñv

Old Cornish: *pluf

Middle Cornish: pluv, plyv

Cornish: pluv

Old Welsh: *plum

Middle Welsh: plu, plvf

Welsh: plu, pluf

Borrowed from Latin plūma (“feather, plume”). Parallel borrowing with Old Irish clúm (“feathers”).


plʉβ̃ọg

Old Breton: plumoc

Middle Breton: pluffec

Breton: pluñveg

Old Cornish: plufoc

→ Cornish: pluvek (semi-learned)

Old Welsh: plumauc

>? Welsh: pluog (possibly re-coined in Modern Welsh)


Sėɨs

*Sėɨs m (feminine *Saɨsnes, plural *Saɨson)

Middle Breton: Saus

Breton: Saoz

Cumbric:

→ English: Pennersax

Middle Cornish: *Seys (attested in personal name)

Cornish: Sows

Middle Welsh: Seis

Welsh: Sais

From earlier *Saxsī, borrowed from Latin Saxō, itself borrowed from Proto-West Germanic *sahsō. Parallel borrowing with Middle Irish Saxa.


Saɨson

Middle Breton: Saoson

Breton: Saozon

Middle Welsh: Saesson

Welsh: Saeson

From earlier *Saxsones, the regular plural of the n-stem *Saxsī. Not directly from Latin Saxōnēs, as this would instead have resulted in **Saɨsʉn.


lleɣenn

Middle Breton: lenn, leenn

desc

⇒ Middle Breton: lenn, leenn (“to read”)

Breton: lenn

Middle Cornish: lyen

Cornish: lien

Middle Welsh: lleen, llen

Welsh: llên

Borrowed from Latin legendum, legendā. Parallel borrowing with Old Irish léigenn (“studying, learning”).


brėx

Middle Breton: brech

Breton: brec'h

Old Cornish: brech

Middle Cornish: bregh

Cornish: bregh

Middle Welsh: breich

Welsh: braich

Borrowed from Latin bracchium. Parallel borrowing with Irish brac (“arm”).


kawl

Middle Breton: caul pl, caoll pl

Breton: kaol pl

Old Cornish: caul

→ Cornish: kowl (semi-learned)

Middle Welsh: kawl

Welsh: cawl
→ English: cawl

Borrowed from Latin caulis. Parallel borrowing with Irish cóilis (“cabbage”).


kantuɨll

Middle Breton: cantoell

Breton: kantol

Old Cornish: cantuil

Middle Cornish: kantyll

Cornish: kantl

Middle Welsh: canhwyll

Welsh: cannwyll

Borrowed from Vulgar Latin *cantēlla, *cantēla, from Latin candēla. Parallel borrowing with Old Irish caindel.


gwenuɨn

Old Cornish: *guenoin

⇒ Old Cornish: guenoin-reiat

Middle Welsh: gwenwyn

Welsh: gwenwyn


paraduɨs

Middle Breton: paradoes, barados, barazoes, baradoes

Breton: baradoz, paradoez, baraouiz (Gwenedeg)

Middle Cornish: parathys, paradys

Cornish: paradhis

Middle Welsh: paradwys

Welsh: paradwys

Borrowed from Vulgar Latin *paradēsus, from Latin paradīsus. Parallel borrowing with Middle Irish pardus (“paradise”).


kaduɨr

Middle Breton: cadoer

Breton: kador

Middle Cornish: *gadoer

Cornish: cadar

⇒ Middle Cornish: Pengadoer

Middle Welsh: cadeir

Welsh: cadair

Borrowed from Latin cathedra. Distantly related Proto-Brythonic *heðɨd (“to sit”), *nɨθ (“nest”). Parallel borrowing with Old Irish cathaír (“chair”).


pluɨβ

Breton: ploue

Cornish: pluw

Middle Welsh: plwyf

Welsh: plwyf

Borrowed from Latin plēbēs (“common people”).


spɨrɨd

Breton: spered

Middle Cornish: sperys

Cornish: spyrys

Middle Welsh: yspryt

Welsh: ysbryd

Borrowed from Latin spīritus. Parallel borrowing with Old Irish spirut (“spirit”).


rruɨd

Breton: roued

Old Cornish: ruid

Cornish: rūz

Middle Welsh: rwyd

Welsh: rhwyd


manax

Breton: manac'h

Old Cornish: manach

Cornish: manah

Middle Welsh: manach, menach

Welsh: mynach

→? Old Irish: manach (see there for further descendants)

Borrowed from Latin monachus. Parallel borrowing with Old Irish manach.


meβ̃or

Old Breton: memor

Breton: eñvor (doublet with memor)

Middle Cornish: myfyr

Borrowed from Latin memoria. Parallel borrowing with Old Irish mebuir (“recollection, memory”).


diskɨnnɨd

Breton: diskenn

Middle Cornish: dyyskynna

Cornish: diyskynna

Middle Welsh: diskynn

Welsh: disgyn

Borrowed from Latin dēscendō and readjusted with the cognate native prefix *di- (“from, of”).


kluɨreg

Breton: kloarek

Old Cornish: cloireg

Cornish: klorek

Borrowed from Latin clēricus. Parallel borrowing with Welsh clerig (“cleric”), Old Irish clérech (“cleric, clerk, scholar”).


parọd

Middle Breton: paret (“boiled”)

Breton: pared (“boiled”)

Old Cornish: parot

Middle Cornish: parys

Cornish: parys

Middle Welsh: parawt

Welsh: parod


rruɨβ̃

Middle Breton: reuff, roeuff

Breton: roeñv

Old Cornish: ruif

Cornish: rêv

Middle Welsh: rwyf

Welsh: rhwyf

Borrowed from Latin rēmus. Doublet of *rrọβ (“shovel, spade”), cognate with Old Irish rámae (“oar, spade”).


uβ̃ɨl

Middle Breton: uuel, vuhel

Breton: uvel

Old Cornish: huuel

Cornish: uvel, huvel

Old Welsh: humil

Middle Welsh: uwyl, uffyl

desc

with ll from <i class="Latn mention" lang="cy">ufylltod</i>

Welsh: ufyll (with ll from ufylltod), hufyll (with h reimported from Latin)

Borrowed from Latin humilis, ultimately from Proto-Indo-European *dʰéǵʰōm (“earth; human”), whence related Proto-Brythonic *dün (“person”). Parallel borrowing with Old Irish umal (“humble”).


skuβarn

Old Breton: *scobarn (in compound)

Middle Breton: scouarn

Breton: skouarn

Old Cornish: scouarn

desc

Middle Cornish: scovern, scovorn, scoforn

Cornish: skovarn

Middle Welsh: ysgyuarn, hyscyfarn

Welsh: ysgyfarn

Unknown. The first element may ultimately be derived from Proto-Indo-European *(s)kewh₁- (“to observe, perceive”).


skuβarnọg

Middle Breton: scouarnec

Breton: skouarneg

Old Cornish: scouarnoc

Cornish: skovarnek

→ English: scavernick

Middle Welsh: yscyfarnawc, ysgyuarnauc

Welsh: ysgyfarnog


gwuɨl

Breton: gouel

Cornish: goel

Middle Welsh: gwyl

Welsh: gŵyl

From earlier *gwēl, from *gwɨɣl, borrowed from Vulgar Latin viglia, from Latin vigilia (“watch, vigil”). Parallel borrowing with Old Irish féil (“festival, feast day”), Middle Irish figel, figell (“vigil”).


gwuɨl

Breton: gouel

Middle Cornish: goyl

Borrowed from Latin vēlum (“curtain, veil; sail of a ship”). Parallel borrowing with Old Irish fíal (“veil, curtain”).


arxangel

Middle Breton: archael

Breton: arc'hael

Old Cornish: archail

Middle Welsh: archangel

Welsh: archangel

Borrowed from Latin archangelus. Parallel borrowing with Old Irish arc(h)aingel.


kuɨr

Breton: koar

Old Cornish: coir

Cornish: kor

Middle Welsh: cwyr

Welsh: cwyr

Borrowed from Latin cēra (“wax”). Parallel borrowing with Old Irish céir (“wax”).


kuɨn

Breton: koan

Cornish: cean

Middle Welsh: cwyn


bʉal

Middle Breton: bual

Breton: bual

Cornish: bual

Middle Welsh: bual

Welsh: bual

Borrowed from Latin būbalus (“buffalo, antelope”). Parallel borrowing with Old Irish búaball (“buffalo”).


Nọdọlɨg

Old Breton: Notolic

Middle Breton: Nedelec

Breton: Nedeleg

Middle Cornish: Nedelic

Middle Welsh: Nodolyc, Nodolic

Borrowed from Latin nātālicius, nātālicia (“birthday”). Doublet of *Nadọlɨg. Parallel borrowing with Old Irish Notlaic (“Christmas”).


Nadọlɨg

Middle Cornish: Nadelic

Cornish: Nadelik, Nadelyk

desctree

Middle Welsh: Nadolyc, Nadolic, Nodolyc
Welsh: Nadolig

Old Breton: Notolic

Middle Breton: Nedelec

Breton: Nedeleg

Borrowed from Vulgar Latin nătālicius, nătālicia, from Latin nātālicius, nātālicia (“birthday”) with pretonic shortening of ā. Doublet of *Nọdọlɨg.


hüβol

Middle Breton: hual

Breton: hual, fuul

Old Welsh: fual

Middle Welsh: hual

Welsh: hual, (obsolete) fuul

From earlier *hwiβol, borrowed from Vulgar Latin fĭbula, from Latin fībula (“clasp, buckle, fetter”). Parallel borrowing with Old Irish sibal, siball (“clasp, buckle”).


gwesper

Breton: gousper, gosper, guesper

Cornish: gwesper

Welsh: gosber, gosper

PIE word
 *wek(ʷ)speros
Borrowed from Latin vesper (“evening, vesper”). Doublet of *ʉxer (“evening”). Possible parallel borrowing with Old Irish fescor (“evening, vesper”), if not inherited from Proto-Celtic *weskʷeros.


geβ̃ell

Breton: gevell

Cornish: gevell, gevelles

Middle Welsh: gefell, geuell

Welsh: gefell, gefeilles

Borrowed from Latin gemellus (“twin”). Proto-Celtic doublet with *yemonos (“twin”), whence Old Irish emon.


tuɨg

Breton: toag

Old Welsh: tuic

Middle Welsh: twyg

Welsh: twyg

Borrowed from Latin thēca (“a case, envelope, sheath”). Parallel borrowing with Old Irish tíag (“wallet, satchel”), and Irish tiach (“theca”).


suɨβ̃

Middle Breton: soaff, soa

Breton: soav

Middle Cornish: soa

Cornish: soov

Middle Welsh: swyf

Welsh: swyf

Borrowed from Latin sēbum (“tallow, grease”). Parallel borrowing with Irish saim (“lard”), Cornish seym, and Welsh saim, all through Old French saim (“fat”).


arọd

Middle Breton: euret

Breton: eured

Cornish: areth

Middle Welsh: arawt

→ Old Irish: oráit

Borrowed from Vulgar Latin *arātiō, from Latin ōrātiō (“speech; prayer”).


pexad

pexaβ̃ (first-person indicative present singular)
pexað (indicative present second-person singular)
pexad (indicative present singular third-person)
pex (conjunct indicative present singular third-person)
pexador (impersonal indicative present)
pexar (conjunct impersonal indicative present)
pexamm (first-person indicative plural present)
pexad (indicative plural present second-person)
pexant (indicative plural present third-person)
pexantor (impersonal indicative present)
pexėss (first-person indicative preterite singular)
pexėssɨð(?) (indicative preterite second-person singular)
pexėssɨd (indicative preterite singular third-person)
pexass (conjunct indicative preterite singular third-person)
pexėdɨd (impersonal indicative preterite)
pexad (conjunct impersonal indicative preterite)
pexassomm (first-person indicative plural preterite)
pexassed (indicative plural preterite second-person)
pexassont (indicative plural preterite third-person)
pexėdėnt (impersonal indicative preterite)
pex (imperative present second-person singular)
pexad (imperative present singular third-person)
pexador (imperative impersonal present)
pexamm (first-person imperative plural present)
pexad (imperative plural present second-person)
pexant (imperative plural present third-person)
pexantor (imperative impersonal present)

Middle Breton: pechiff

Breton: pec'hiñ

Middle Cornish: pecha

Cornish: pegha

Middle Welsh: pechu

Welsh: pechu


pexadʉr

Middle Breton: pechezr

Breton: pec'her

Middle Cornish: pechadur, pehadur

Cornish: peghador

Middle Welsh: pechadur

Welsh: pechadur

Borrowed from Vulgar Latin peccătōrem, from Latin peccātōrem with pretonic shortening of ā. Equivalent to *pexọd (“sin”) or *pexad (“to sin”) + *-adʉr.


pexọdow

Middle Breton: pechedou

Breton: pec'hedoù

Middle Cornish: peghosow, peghusow

Middle Welsh: pechodeu

Welsh: pechodau


streɨl

Old Cornish: streil

Cornish: streil

From earlier *streɣl, borrowed from Vulgar Latin *strigla, from Latin strigula, strigilis (“strigil”).


-adʉr

Old Breton: -adur

Middle Breton: -adur

Breton: -adur

Old Cornish: -adur

Middle Cornish: -adur

Cornish: -ador

Old Welsh: -adur

Middle Welsh: -adur

Welsh: -adur

Borrowed from Latin -ātor. Parallel borrowing with Old Irish -atóir.

Forms nouns denoting a tool or instrument.


maguɨr

Old Breton: macoer

Breton: moger, magoar

Middle Welsh: magwyr

Welsh: magwyr

Borrowed from Vulgar Latin măcēria, from Latin mācĕria (“wall”). Parallel borrowing with Middle Irish macre (“wall trowel”).


aβuɨn

Cornish: avond

Middle Welsh: afwyn

Welsh: awen

Borrowed from Latin habēna (“thong, rein, lash, bridle”). Related to *gaβl (“fork”). Parallel borrowing with Middle Irish abann (“scourge, whip”).


strodʉr

Old Welsh: strotur

Middle Welsh: estrodur

Welsh: ystrodur

Borrowed from Vulgar Latin strătūra, from Latin strātūra (“saddle”). Parallel borrowing with Old Irish srathar (“pack-saddle”).


kʉβɨgl

Middle Welsh: kudygyl

Welsh: cuddygl, cufygl (doublet with ciwbicl)

Borrowed from Latin cubīclum, cubiculum (“small bedroom; bedchamber”). Parallel borrowing with Middle Irish cubachail (“cubicle, small bedchamber”).


paruɨd

Old Cornish: poruit

Middle Welsh: parwyt, paraet, paret

Welsh: pared

Borrowed from Late Latin parēs (“wall”).


mėnɨβr

Welsh: menebyr, menybyr, mynebr, mynyhr

Borrowed from Latin manĭbrium, manūbrium (“handle, haft”).


neɨθjọr

Middle Welsh: neithiawr

Welsh: neithiawr

From earlier *nexθjọr, borrowed from Latin nūptiālia (“wedding feast”).


munβ̃ent

Middle Welsh: mynwent

Welsh: mynwent

Borrowed from Latin monumenta, nominative plural of monumentum (“memorial, monument, tomb”). Cognate with *menw (“thought, mind”). Parallel borrowing with Middle Irish monameint (“monument”).


menw

Middle Breton: meno

Breton: meno

Middle Welsh: mynw

Welsh: mynw


korruɨ

desc

Middle Breton: *correu (plural), correenn (singulative)

Old Welsh: corruui

Middle Welsh: carryeu, carreieu, carrei, carei

Welsh: carrai

Disputed; possibly either:
* borrowed from Latin corrigia, conrigia (“shoe-string; whip-lash, rein”), perhaps through Vulgar Latin *correia, if not itself borrowed from Celtic;
* or inherited from Proto-Celtic *kom-ɸro-rig-ā, from *kom- (“with”) + *ɸro- (“before”) + *rigeti (“to bind”) + *-ā.


gwɨrθ

Old Welsh: guirdou pl

Middle Welsh: guirth, gwyrth

Welsh: gwyrth

Borrowed from Latin virtūs (“manhood, virtue”). Cognate with *gwur (“man, husband”). Parallel borrowing with Old Irish firtu (“miracle”), and perhaps Gaulish *uiridos, attested in various personal names.


axọs

Middle Welsh: achaws

Welsh: achos

Borrowed from Latin occāsiō (“occasion, opportunity”). Parallel borrowing with Cornish acheson (“occasion, reason”), Old Irish accuis (“cause, reason”).


trindọd

Breton: trinded

desc

Cornish: trindas, trinsys, trengys, trenses

Old Welsh: trintaut

Middle Welsh: trindawt, trindod

Welsh: trindod

→ Old Irish: tríndóit

Irish: trindaid

Manx: trinaid

Scottish Gaelic: trionaid, trianaid

Borrowed from Latin trīnitātem, accusative singular of trīnitās (“Trinity”).


bendiθ

Middle Breton: bennoz, bennoez

Breton: bennozh

Middle Cornish: bennath, benneth

Cornish: bednath

Middle Welsh: bendith

Welsh: bendith

From earlier *bendɨxθ, borrowed from Latin benedictiō, benedictum (“blessing, benediction”). Parallel borrowing with Old Irish bendacht (“blessing, benediction”).


maluɨn

Middle Welsh: malaen

Welsh: malen

From earlier *malɨɣn, borrowed from Latin malignus (“wicked, malicious”), syncopation of malus (“bad”) + genus (“kind”), doublets of Proto-Celtic *mellos (“destruction, confusion”) and *genos (“family; birth”).


eβengɨl

Breton: aviel

Old Cornish: aweil

Middle Cornish: awayl

Cornish: aweyl

Middle Welsh: euegyl, *efengyll

Welsh: efengyl, efangel, efangyl

Borrowed from Latin evangelium (“gospel”), itself borrowed from Ancient Greek εὐαγγέλιον (euangélion, “bringing good news”), from εὐ- (eu-, “good”) + ἄγγελος (ángelos, “messenger”), equivalent to *hu- (“good”) + *angel (“angel, messenger (of God)”). Old Irish adopted the calque soiscélae, from so- (“good”) + scél (“news”).


dinėr

Breton: diner

desc

Cornish: dinair, dinar, diner, dynar, dyner, dynnar

Welsh: dinair

Borrowed from Vulgar Latin dēnărius, from Latin dēnārius (“denary”).


profuɨd

Breton: profed

Cornish: profus, profuit

Welsh: proffwyd

Borrowed from Latin prophēta (“prophet”).


tɨner

Breton: tener

Middle Welsh: tyner

Welsh: tyner

Borrowed from Latin tener (“soft, tender, delicate”). Parallel borrowing with Cornish tender (“sensitive, tender”).


ọr

Old Breton: or

Middle Breton: eur

Breton: eur

Cornish: our

Old Welsh: aur

Middle Welsh: awr

Welsh: awr

Borrowed from Latin hōra (“hour”). Parallel borrowing with Old Irish úar, úair (“hour”).


abrant

Breton: abrant

Cornish: abrans

Middle Welsh: amrant

Welsh: amrant


lloβ̃an

Middle Breton: louffan

Breton: louan

Cornish: lovan

Middle Welsh: llyfan

Welsh: llyfan


taβern

Breton: tavarn

Cornish: tavern

Middle Welsh: tauarn

Welsh: tafarn

Borrowed from Latin taberna (“inn”). Parallel borrowing with Irish tábhairne (“tavern”).


ʉxer

Old Cornish: *uher

⇒ Old Cornish: gurthuher

Cornish: gorthugher

Middle Welsh: ucher, uchyr

Welsh: ucher

From earlier *wixer, from Proto-Celtic *weskʷeros. Doublet of *gwesper (“evening”).


exuɨð

Breton: ec'hoaz

Cornish: ewhe

Welsh: echwydd

From earlier *ekkēdos or similar, of unknown origin; possibly related to Old Irish adaig (“night”), from earlier *adek(ʷ)ī, whose etymology is also obscure.


huɨr

Middle Welsh: hwyr

Welsh: hwyr

Early borrowing from Latin sērus (“late, slow”). Doublet of *hir (“long, tall”).


neɨθjuɨr

Middle Breton: neyzor

Breton: neizheur, neizhour

Cornish: nyhewer, nehuer

Middle Welsh: neithiwyr, neithwyr

Welsh: neithiwr

Uncertain; possibly from:
* *noɨθ (“night”), from Proto-Celtic *noxs, + *huɨr (“late”);
* or borrowed from unattested Vulgar Latin *noxtiōr, from Proto-Indo-European *nókʷt-yōs, from *nókʷts (“night”) + *-yōs, cognate with Albanian nesër (“tomorrow”).


henoɨθ

Middle Breton: hanoez

Breton: henoazh

Middle Cornish: haneth

Old Welsh: henoid

Middle Welsh: heno

Welsh: heno


ʉθ

Middle Breton: euz

Breton: euzh

Cornish: uth, euth

Welsh: uthr

From Proto-Celtic *(ɸ)owtus, *awtus, possibly related to *oβn (“fear”). Cognate with Old Irish úath (“hate”).


oβn

Middle Breton: oun

Breton: ovn

Cornish: own

Middle Welsh: ofuyn

Welsh: ofn

From Proto-Celtic *(ɸ)oβnus, possibly related to *ʉθ (“horror”). Cognate with Old Irish ómun (“fear”).


mennɨd

Middle Breton: mennat

Breton: menniñ, mennouta

Cornish: mynnes

Welsh: mynnu

From Proto-Celtic *menneti, from Proto-Indo-European *mén-dʰh₁e-ti, from *men- (“to think”).


niθjɨd

Middle Breton: niza

Breton: nizhañ

Middle Welsh: nithiaw

Welsh: nithio


llenn

Old Breton: lenn

Breton: lenn

Old Cornish: len

Cornish: len

Old Welsh: lenn

Middle Welsh: llen

Welsh: llen

From Proto-Celtic *linnā. Cognate with Old Irish lenn (“cloak”).


diaβul

Middle Breton: diaoul

Breton: diaoul

Cornish: dyowl, dyaul, jawl

Old Welsh: diaul

Middle Welsh: diawl, diauul

Welsh: diawl, diafol

Borrowed from Latin diabolus. Parallel borrowing with Old Irish díabul (“devil”).


kiwdọd

Middle Breton: queudet

Breton: keoded

Middle Welsh: kiwdawt

Welsh: ciwdod

Borrowed from Vulgar Latin *[kiwˈtate~kiβˈtate], from Latin cīvitātem, accusative singular of cīvitās (“citizenry; city”). Doublet of *kiwed, from the nominative singular, whence Welsh ciwed.


llɨβr

Old Breton: libr

Middle Breton: leor

Breton: levr

Middle Cornish: lyver

Cornish: lyver

Middle Welsh: llyuyr

Welsh: llyfr

Borrowed from Vulgar Latin lĭbrum, from Latin lībrum, accusative singular of līber (“book”). Parallel borrowing with Old Irish lebor (“book”).


tɨɣern

Old Breton: *tiarn, *tiern

Middle Breton: tiern

Breton: tiern

Old Welsh: *tigern

Middle Welsh: teern, teyrn

Welsh: teyrn

From Proto-Celtic *tigernos. Cognate with Old Irish tigern (“lord”).


tɨɣernọg

Old Breton: *tiarnoc

Welsh: teyrnog

From Proto-Celtic *tigernākos. Equivalent to *tɨɣern (“lord, ruler”) + *-ọg. Cognate with Old Irish tigernach (“lordly”).


gwolʉd

Middle Welsh: golud

Welsh: golud

From Proto-Celtic *uɸolautom (“wealth, property”). Cognate with Old Irish folud (“wealth”).


gwolʉdọg

Old Cornish: wuludoc

Welsh: goludog


tėnėw

Middle Breton: tanau, tanow

Breton: tanav

Old Cornish: tenewen

Cornish: tanaw

Old Welsh: teneu

Middle Welsh: teneu

Welsh: tenau


eðenn

Middle Breton: ilieavenn

Breton: iliav, ilio, iliavenn (sgv.)

Cornish: idhyow, idhyo, idhyowen (sgv.)

Middle Welsh: eido, eiddio

Welsh: eiddew, eiddo

From Proto-Celtic *edennos. Cognate with Old Irish eidenn (“ivy”).


eβur

Middle Breton: heuor, euor

Breton: evor (“alder buckthorn”)

Cornish: evor (“hogweed”)

Middle Welsh: efwr, ewr

Welsh: efwr (“hogweed, cow parsnip”)

From Proto-Celtic *eburos (“yew”). Cognate with Old Irish ibar (“yew”).

The meaning of this term is uncertain. Possibilities include: yew, cow parsnip, hogweed, buckthorn


assow

Middle Breton: hasou, hasaou

Breton: so, sou, asou

Middle Welsh: asswy, aswy (< *assuɨ), asu, asseu

From Proto-Celtic *assouyā f, *assouyos m, from *ad- (“to, at, towards”) + *souyos (“left”).


lluss

Middle Breton: lousaou pl

Breton: louzoù

Old Cornish: les

Middle Cornish: leys sg, losow pl

Cornish: les sg, losow pl

Middle Welsh: llysyeu pl

Welsh: llys sg, llysiau, llysau pl


dexowluss

Middle Breton: dehoules

Welsh: deheulys

From *dexow (“southern”) + *lluss (“herb”). Possible calque of Old English sūþernewudu (“southernwood, wormwood”).


bux

Middle Breton: bouch

Breton: bouc'h

Old Cornish: boch

Middle Welsh: bwch

Welsh: bwch


bʉ

Breton: bu

Middle Welsh: bu, buw


bʉx

Breton: buoc’h

Old Cornish: buch

Middle Cornish: bugh

Cornish: bugh

Middle Welsh: buch

Welsh: buwch

Modified from *bʉ (“cow”) under the influence of other animal names ending with *-x, such as *bux (“goat”), *hux (“pig”), *mox (“pigs”).


kunikl

Middle Breton: conicl, conniffl

Breton: konikl, konifl


pɨg

Old Breton: pic

Middle Breton: pec

Breton: pec, peg

Welsh: pyg

Cornish: peg

Borrowed from Latin pix. Parallel borrowing with Irish pic (“pitch, tar”).


skudell

Breton: skudell

Cornish: skudel

Welsh: ysgudell


ʉβ̃ɨldọd

Middle Breton: uveltet

Old Cornish: huveldot

Middle Welsh: uvildaud

Welsh: ufylltod, ufulltod

Borrowed from Latin humilitātem. Parallel borrowing with Old Irish humaldóit, umaldóit (“humility”).


koluɨn

Breton: kolen

Old Cornish: coloin

Cornish: kolen

Welsh: colwyn

From Proto-Celtic *kolignos, possibly of non-Indo-European origin.


brọdr

Old Breton: brotr

Middle Breton: breuzr

Breton: breur

Old Welsh: braut

Welsh: brawd

Cornish: broder

From Proto-Celtic *brātīr. The loss of the -ī- in the singular is regular.


Prɨdėn

Possibly from Proto-Indo-European *kʷer- (“to do”).


Kunoβ̃ọr

⇒? Breton: Tregonveur, Plougonveur

Old Welsh: Conmor (early)

Middle Welsh: Kynvawr, Kynwawr

Welsh: Cynfawr (historical)

desc

→ Latin: Conomorus, Cunomorus, Quonomorius

→ English: Conomor

→ French: Conomor

From *kun- (“dog”, oblique stem) + *mọr (“great”), literally “big dog”.


marxad

Old Breton: marchat

Middle Breton: marchat

Breton: marc'had

Middle Cornish: marghas

Borrowed from Vulgar Latin marcatus, from Late Latin marcātus, from Latin mercātus.


skʉbọr

q

attested in the place name <i class="Latn mention" lang="xbm">Squiber Nevez</i>

Middle Breton: *squiber (attested in the place name Squiber Nevez)

Breton: skiber

Middle Cornish: skyber

Cornish: skiber

Old Welsh: scipaur

Middle Welsh: yscubawr

Welsh: ysgubor, sgubor

→ Irish: scioból

From British Latin *scōpārium, from scōpa (“branch, sheaf”).


furn

Old Cornish: forn

→ Cornish: forn

Middle Breton: forn

Middle Welsh: ffwrn

Welsh: ffwrn

desctree

→ Old Irish: sorn, sornn
Irish: sorn
Manx: sorn
Scottish Gaelic: sòrn
→ Faroese: sornur
→ Norwegian Nynorsk: sonn


llɨθer

Middle Breton: lizer

Breton: lizher

Middle Cornish: lyther

Cornish: lyther

Old Welsh: leder

Middle Welsh: llythyr

Welsh: llythyr

letter (symbol in an alphabet; written or printed communication)