tail end

the part of the body upon which someone sits all I saw was his tail end vanishing around the door Synonyms backside, behind, booty (also bootie) [slang], bottom, breech, bum, buns, butt, caboose, can, cheeks, derriere (or derrière), duff, fanny, fundament, hams, haunches, heinie [slang], hunkers, keister (also keester) [slang], nates, posterior, rear, rear end, rump, seat, tail, buttocks, tush [slang]Related Words beam, stern; moon [slang]