Words for sack, bag, stomach in Celtic languages.

| Proto-Celtic |
*bolgos = sack, bag, stomach |
| Gaulish |
*bolgā = sack, bag, stomach |
| Old Irish (Goídelc) |
bolc = belly, stomach; bag, satchel; bellows |
| Irish (Gaeilge) |
bolg [ˈbˠɔlˠəɡ] = belly, stomach, abdomen; bag; bulge, broad part, middle; bellows
bolgach = big-bellied, bulging
bolgadán = corpulent person or animal
bolgán = bubble, bulb, air-bladder (of fish), puff-ball, windbag (of person)
bolgchaint = ventriloquism |
| Scottish Gaelic (Gàidhlig) |
bolg [bɔl̪ˠɔg] = blister, bulge, (light) bulb
bolgach = abounding in bags/blisters, bellied, bulging, jutting, knobby
bolgadh = billowing, puffing up/out, ballooning, swelling
bolgan = (plant) bulb, lightbulb |
| Manx (Gaelg) |
bolg [bolɡ] = stomach, abdomen, belly, tummy, corporation, bilge, bowl (of lamp)
bolgagh = abdominal, bellied, billowy, blisterm bulging, puffy
bolgan = bladder, blister, sac, vesicle, bubble |
| Proto-Brythonic |
*bolɣ = sack, bag, stomach |
| Old Welsh |
bolg = belly, stomach |
| Middle Welsh (Kymraec) |
bol, boly = belly, stomach |
| Welsh (Cymraeg) |
bol = belly, paunch, abdomen, stomach, bowels; tripe; appetite, desire, gluttony, liking; womb; swelling, bulge, surface, side
bolio = to gorge, belly, swell, bulge, swagger
boliog = (big-)bellied, corpulent, swollen, bulging, pregnant |
| Cornish (Kernewek) |
bolgh [bɔlx] = breach, gap, opening
bolghen = boll, capsule |
| Middle Breton |
bolc’h = flax pod |
| Breton (Brezhoneg) |
bolc’h = flax pod |
Etymology
From Proto-Indo-European *bʰólǵʰ-os (skin bag, bolster), from *bʰelǵʰ- (to swell) [source].
English words from the same PIE root include bellows, belly, and bolster, via Old English and Proto-Germanic, billow via Old Norse and Proto-Germanic, foolish and folly via Old French and Latin [source], and bulge, budge and budget via Old French, Latin and Gaulish [source].
Words marked with a * are reconstructions.
Sources: Wiktionary, Am Faclair Beag, Online Manx Dictionary, Teanglann.ie, Geiriadur Prifysgol Cymru, Gerlyver Kernewek, Dictionnaire Favereau