עָצֶה, v. עֲצֵי) backbone, spine. Sifra Vayikra, N’dab., Par. 14, ch. XIX (ref. to Lev. IV, 9) יכנס לפנים מן הע׳ he must go inside of the backbone, i.e. cut off a portion of the spine; Yalk. Lev. 462.