[breech] n [ME, breeches, fr. OE brec, pl. of broc leg covering; akin to OHG bruoh breeches, L braca pants] (bef. 12c) 1 pl a: short pants covering the hips and thighs and fitting snugly at the lower edges at or just below the knee b: pants
2. a: the hind end of the body: buttocks b: breech presentation; also: a fetus that is presented breech first
3: the part of a firearm at the rear of the barrel