What is another word for "heelpiece"?

Roget's Thesaurus (1911) lists these synonyms for "heelpiece": aback, abaft, aft, after, aftergame, aftergrowth, afterpiece, afterthought, aitchbone, appendage, appendix, arriere, astern, back, background, backside, backwards, behind, bend, bone, breech, bring, buttock, caudal, chine, codicil, coin, colophon, continuation, croup, crupper, dorsal, dorsum, epilogue, fall, guard, hind, hinder, hindermost, hindmost.