Open English Wordnet
Nouns
(n)buttocks, nates, arse, butt, backside, bum, buns, can, fundament, hindquarters, hind end, keister, posterior, prat, rear, rear end, rump, stern, seat, tail, tail end, tooshie, tush, bottom, behind, derriere, fanny, assthe fleshy part of the human body that you sit on“he deserves a good kick in the butt”, “are you going to sit on your fanny and do nothing?”