body part vs body structure

Other hyponyms of body part include saddle, underpart, horseback, dock, ambulacrum, withers, cannon, shank, loin, lumbus, croup, croupe, hindquarters, rump, gaskin, flank, thorax, apparatus, adnexa, annexa, area, region, dilator, groove, vallecula, partition, external body part, anatomical structure, bodily structure, complex body part, structure, fornix, system, ampulla, tissue, mentum, organ, venter, energid, protoplast, appendage, outgrowth, process, lobe, rectum, shoulder, body, torso, trunk, chest, pectus, thorax, thorax, hip, haunch, abdomen, belly, stomach, venter, dorsum, back, dorsum, small, arse, ass, backside, behind, bottom, bum, buns, butt, buttocks, can, derriere, fanny, fundament, hind end, hindquarters, keister, nates, posterior, prat, rear, rear end, rump, seat, stern, tail, tail end, tooshie, tush, buttock, cheek, stump, shank, shin, toe, articulatio, articulation, joint, loins, feature, lineament, rudiment.