The Collaborative International Dictionary of English v.0.48:
Triquetral \Tri*que"tral\, a. Triquetrous. [1913 Webster]WordNet (r) 3.0 (2006):
triquetral n 1: a wrist bone that articulates with the pisiform and hamate and lunate bones [syn: triquetral, triquetral bone, os triquetrum, cuneiform bone, pyramidal bone]