"posteriors" in the noun sense
1. 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, ass
the 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?"
2. back tooth, posterior
a tooth situated at the back of the mouth
Source: WordNet® (An amazing lexical database of English)
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