Words for deer in Celtic languages. There were several different words for deer in Proto-Celtic: *wēdus, *karwos, *ellan(t)ī-, *danī- and *yorkos, and also *sidos (stag). They may have referred to different types of deer, but it is not certain which types, apart from *yorkos, which is a roe deer.

Words marked with a * are reconstructions.
| Proto-Celtic |
*wēdus [ˈweː.dus] = wild |
| Old Irish (Goídelc) |
fíad [fʲiːa̯ð] = wild animals, game, especially deer |
| Middle Irish (Gaoidhealg) |
fíad, fiad = wild animals, game, esp. deer
fíadamail = deer-like, wild, uncultivated |
| Irish (Gaeilge) |
fia [fʲiə] = deer |
| Scottish Gaelic (Gàidhlig) |
fiadh [fiəɣ] = deer
fiadhach [iə.əx] = deer hunting, venision, wildness, wilderness
fiadhachadh = deer hunting |
| Manx (Gaelg) |
feeaih, feeaïh = deer, hart
feeaihagh = deer hunting
feeaihaght = deer hunt |
Etymology: from the Proto-Indo-European *weydʰ- (wood, wilderness) [source].
| Proto-Celtic |
*karwos = deer, stag |
| Gaulish |
caruus, carvos, *caruos = deer |
| Old Irish (Goídelc) |
carbh = deer |
| Middle Irish (Gaoidhealg) |
cairrḟiad, cairrfiadh = stag |
| Irish (Gaeilge) |
carria / cairrfhiadh = deer, stag |
| Scottish Gaelic (Gàidhlig) |
cair-fhiadh / carbh-fheadh = hart, stag |
| Manx (Gaelg) |
çharroo, charroo = stag |
| Proto-Brythonic |
*karw = deer, stag |
| Old Welsh |
*caru = deer |
| Middle Welsh (kymraec) |
caru, carv, keyru, carw, karw = deer, hart, stag
carwaidd = having the attributes of a stag, pertaining to a stag, noble, wise
carwnaid, karwnaid = stag’s leap, a great leap |
| Welsh (Cymraeg) |
carw [ˈkaru / ˈkaːru] = deer, hart, stag; lord, nobleman, patron
carw coch / carw rhudd = red deer, stag
carw Llychlyn = reindeer
carwfarch = camel, elephant
carwfil = stag, camel |
| Old Cornish |
caruu = stag |
| Middle Cornish |
carow = stag |
| Cornish (Kernewek) |
karow = stag, buck, hart, stag
karow ergh = caribou, reindeer
karow rudh = red deer |
| Middle Breton |
caro, carv, caru = deer |
| Breton (Brezhoneg) |
karv [ˈkarw / ˈkɑːro] = deer, roe deer, red deer
karv-erc’h = caribou, reindeer
karvez = doe
karvig = fawn
karvken = deer hide |
Etymology: from Proto-Indo-European *ḱerh₂wós, from *ḱerh₂- (horn) [source].
| Proto-Celtic |
*sidos = stag |
| Old Irish (Goídelc) |
séd = deer |
| Middle Irish (Gaoidhealg) |
ség, ség, sedh = deer |
| Middle Welsh (Kymraec) |
hit, hyd, hed, hydd = stag, hart
hyddgarw, hawddgar = stag, deer, lord, patron, wise leader, horse
hyddgen, hydgen = deer-skin, buckskin
hyddgi = buck-hound, stag-hound, greyhound |
| Welsh (Cymraeg) |
hydd = stag, hart
hyddaidd = having the attributes of a stag, cervine
hyddgarw = stag, deer, lord, patron, wise leader, horse
hyddgen, hyddgroen = deer-skin, buckskin
hyddgi = buck-hound, stag-hound, greyhound
hyddgig = venison |
| Cornish (Kernewek) |
hedh = buck, hart, stag |
| Old Breton (Brethonoc) |
hed = deer, fallow deer |
| Middle Breton (Brezonec) |
heizes, eizec = doe, hind |
| Breton (Brezhoneg) |
heizez = doe, hind
heizezig = darling |
Etymology: uncertain
| Proto-Celtic |
*ellan(t)ī- / *agliones = deer |
| Old Irish (Goídelc) |
ag [aɣ] = bullock, cow, ox, deer, stag |
| Middle Irish (Gaoidhealg) |
ag, agh = cow, ox, deer, stag |
| Irish (Gaeilge) |
agh = cow, ox
agh alla = deer
agh dára = cow, ox |
| Scottish Gaelic (Gàidhlig) |
agh [ɤɣ] = heifer, hind |
| Middle Welsh (Kymraec) |
eilon, eilion = deer, hart, stag |
| Welsh (Cymraeg) |
eil(i)on = deer, hart, stag |
Etymology: possible from the same root as the English word eland (a type of antelope found in South Africa), which from the Dutch eland (elk), from the Old High German elent.
| Proto-Celtic |
*ou̯ījkā = ? |
| Gaulish |
cerua = ? |
| Old Welsh |
eguic = hind, deer |
| Middle Welsh (Kymraec) |
eguic, euic, euychet, euchyc, ewic, ewig = deer, hart, stag
ewigaidd = pertaining to hind(s), hind-like |
| Welsh (Cymraeg) |
ewig = hind, doe, roe; graceful light-footed woman; deer, hart
ewigfa = deer-park |
| Old Cornish |
euhic = hind, deer |
| Middle Cornish (Cernewec) |
ewic, euhic, ewig = hind, deer |
| Cornish (Kernewek) |
ewik = deer, doe, hind
ewik ergh = caribou, reindeer
ewik gowr = elk, moose
ewik rudh = red deer |
Etymology: possibly from the Proto-Indo-European *h₂ówis (sheep) [source]
| Proto-Celtic |
*yorkos = roebuck, deer |
| Gaulish |
iorkos, iorcos = deer |
| Proto-Brythonic |
*jorx = deer, stag |
| Welsh (Cymraeg) |
iwrch [jʊrχ] = roe-deer, roebuck |
| Old Cornish |
yorch = roe-deer |
| Middle Cornish (Cernewec) |
iorch, yorch = roe buck
iorches = roe deer |
| Cornish (Kernewek) |
yorgh = roe deer
yorghes = (female) roe deer |
| Old Breton |
iorch = roe deer |
| Middle Breton (Brezonec) |
yourch = roe deer |
| Breton (Brezhoneg) |
yourc’h [ˈjurx] = roe deer, venison, intrepid boy, wild
yourc’hez = (female) roe deer |
Etymology: from the Proto-Indo-European *york- (antelope, gazelle) [source].
| Proto-Celtic |
*danī- = deer |
| Middle Welsh (Kymraec) |
danys, danas = deer, fallow deer |
| Welsh (Cymraeg) |
danas, danys, daenas [ˈdanas] = deer, fallow deer |
| Middle Breton (Brezonec) |
dem = deer, fallow deer |
| Breton (Brezhoneg) |
demm = deer, fallow deer |
Etymology: related to the French daim (hind, doe), from the Latin dāma (fallow deer, buck, doe) [source]
Sources: Wiktionary, Etymological Dictionary Of Proto Celtic, In Dúil Bélrai English – Old Irish glossary, eDIL – Electronic Dictionary of the Irish Language, Teanglann.ie, Am Faclair Beag, An etymological dictionary of the Gaelic language, Fockleyreen: Manx – English Dictionary, Online Manx Dictionary, Gaelg Corpus, Geiriadur Prifysgol Cymru, Lexicon cornu-britannicum : a dictionary of the ancient Celtic language of Cornwall, Gerlyver Kernewek, Devri : Le dictionaire diachronique du breton, Geriafurch, TermOfis