Words for number, to count and related things in Celtic languages.

Words marked with a * are reconstructions.
| Proto-Celtic |
*rīmā = number |
| Old Irish (Goídelc) |
rím [r͈ʲiːβ̃] = counting, enumerating, number, telling, relating, metrics
rímid [ˈr͈ʲiːβ̃ɨðʲ] = to count, reckon, estimate, impute, compose, recount, relate |
| Middle Irish (Gaoidhealg) |
rím = counting, enumerating, number, telling, relating
rímid, rímaid = to count, reckon, estimate, recount, relate, compose |
| Irish (Gaeilge) |
ríomh [ɾˠiːvˠ/ɾˠiːw] = enumeration, calculation, computation, narration
ríomhaire = counter, enumerator, calculator, computer
ríomhaireacht = counting, enumeration, calculation, computation
ríomhchláraitheoir = computer programmer
ríomheolaíocht = computer science |
| Scottish Gaelic (Gàidhlig) |
rìomh† = reckoning, numbering, computation
rìmh† = number, to reckon, compute |
| Proto-Brythonic |
*rriβ̃ = number |
| Middle Welsh (Kymraec) |
rif, yrif, rhif = sum, number, etc
rhifo, riuaw, riuaỽ = to count
rifed, riued, ryved = number, many, abundance |
| Welsh (Cymraeg) |
rhif [r̥iːv] = the sum, number, as many or numerous (as), a (great) many, crowd, host, multitude, large amount, worth, esteem, honour, praise, figure, digit, numeral, count, reckoning, measure
rhifadwy = countable, numerable
rhif(i)o = to count, number, amount to, enumerate, list, recount, enlist, muster
rhifed = number, many, abundance |
| Cornish (Kernewek) |
riv = number
riva = to number
riven = digit |
| Breton (Brezhoneg) |
riñv = number |
Etymology: from the Proto-Indo-European *h₂rey- (to count, reason, think) [source]. Words from the same root include arithmetic, rhyme, rite, ritual and ready in Englsh, reic (to sell in Irish, řádný (regular) in Czech, and rinda (row, line, queue) in Latvian [source].
| Proto-Celtic |
*adrīmā = counting, number, reckoning |
| Old Irish (Goídelc) |
áirem = number, numeral, quantity. amount, sum, reckoning, repute, account |
| Middle Irish (Gaoidhealg) |
áirem, áram, arim, ārem = counting, reckoning, estimating, number, numeral, amount, sum
comáirem, comairem, comairemh = reckoning, calculating, computation |
| Irish (Gaeilge) |
áireamh = enumeration, census, arithmetric, number, portion
comhair = to count, calculate
comhaireamh = to count, calculation, reckoning |
| Scottish Gaelic (Gàidhlig) |
àireamh [aːrʲəv] = number, sum, tally, computation, counting, enumerating; count, enumerate
àireamhach [aːrʲəvəx] = numeral, arithmetician
àireamhachadh [aːrʲəvəxəɣ] = numbering, enumerating, enumeration, calculating, computing, calculation, computation
àireamhail [aːrʲəvəxal] = arithmetical
àireamhachas [aːrʲəvəxəs] = numeracy
àireamhair [aːrʲəvɛrʲ] = calculator (tool), arithmetician |
| Manx (Gaelg) |
earroo = number, sum, figure, census, statistics, tell
co-earroo = calculation, computation, counting, telling, to compute, count
earrooaghey = number(ing)
co-earrooaghey = to calculate, calculating, numbering |
| Proto-Brythonic |
*ėðriβ̃ = (?) |
| Middle Welsh (Kymraec) |
eryryw, eiryf, eirif = number, amount, sum, account, reckoning |
| Welsh (Cymraeg) |
eirif = number, amount, a large number, many, sum, account, reckoning |
| Old Breton (Brethonoc) |
eirimotor = (?) |
Etymology: from the Proto-Celtic *rīmā (number) – see above [source].
| Old Irish (Goídelc) |
uimir = number |
| Middle Irish (Gaoidhealg) |
(n)uimir = number |
| Irish (Gaeilge) |
uimhir [ˈɪvʲəɾʲ / ˈɨ̞̃vʲəɾʲ] = number, count, aggregate
uimhreoir = numerator
uimhrigh = to number, figure
uimhríocht = arithmetic
uimhríochtúil = arithmetical
uimhriú = numbering, numeration, figuring
uimhriúil = numerical, numeral |
| Scottish Gaelic (Gàidhlig) |
uimhir [ɯvɪrʲ] = quantity, amount, number, so/as much/many
fuimhir [fɯvɪrʲ] = quantity, number
uimhireach [ɯvɪrʲəx] = numerous
uimhireach [ɯvɪrʲɪç] = arithmetician |
| Proto-Brythonic |
*niβ̃er = number |
| Old Welsh (Kembraec) |
nimer = number |
| Middle Welsh (Kymraec) |
niuer, niver, nifer = number host, company, retinue, troop, crowd
nifery = to number, enumerate, count
niveredic = counted, numbered
niferawg, niuerawc, nigerog, niverog = numerous, abundant, having hosts, troops, retinues, etc
nifeiriawl, niferawl, niueiriawl = numerous, abundant, numerical
kyfnifer, kyfniuer = as many, equal number, even number, a great many, large number, host |
| Welsh (Cymraeg) |
nifer [ˈnɪvɛr] = number, host, company, retinue, troop, crowd
niferu, nifeirio = to number, enumerate, count
niferedig = counted, numbered
niferadol = numerical, pertaining to a census
nifer(i)og = numerous, abundant, having hosts, troops, retinues, etc
nifer(i)ol = numerous, abundant, numerical
cyfnifer = as many, equal number, even number, a great many, large number, host |
| Middle Cornish (Cernewec) |
never, niver = number
nevera, nivera, nyfyrys = to number, count, reckon
cyniver, cynyver, cenifer, cenyver, ceniver = so many, as many as, every, every one |
| Cornish (Kernewek) |
niver = number
nivera = to count, number
niverek = numerical
niverell = counter, counting device
niveren = numeral
niverenans, niverednans = numbering
niveronieth = arithmetic
niverus = numerous
niveryans = census, count
keniver = as many, everyone, so many |
| Old Breton (Brethonoc) |
nimer = number |
| Middle Breton (Brezonec) |
niuer, nyuer = number
niueraff = to enumerate, number |
| Breton (Brezhoneg) |
niver [ˈniː.vɛr] = number
niveradeg = census
niveradur = ennumeration
niverenn [ni.ˈveː.rɛn] = number
niverennañ = to number
niverer = numerator
nivererezh = numbering
niveridigezh = enumeration, census
niveriñ [niˈveːrĩ] = to enumerate, number
niveroniezh [ˌni.ve.rɔ̃.ˈniː.ɛs] = arithmetic
niverus [ni.ˈveː.rus] = numerous |
Etymology: from Latin numerus (number, collection, quantity, time, rhythm) [source], from Proto-Italic *nomezos, from PIE *nem- (to distribute give, take). Words from the same root economic, numb and number, numeral in English, nemen (to take, grasp, grab) in Dutch, nehmen (to take, hold, grasp), and número (number) in Spanish [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, Dictionnaires bilingues de Francis Favereau / Edition Skol Vreizh, TermOfis