尺骨
Ulna \Ul"na\, n. [L., the elbow. See {Ell}.] 1. (Anat.) The postaxial bone of the forearm, or branchium, corresponding to the fibula of the hind limb. See {Radius}. 2. (O. Eng. Law) An ell; also, a yard. --Burrill.
ulna n : the inner and longer of the two bones of the human forearm [syn: {elbow bone}] [also: {ulnae} (pl)]