a group of small, somatic, motor neurons in the ventral horn of the spinal cord at sacral 2 level that innervate the vesicorectal sphincters, i.e., the external anal and the urethral sphincter; Onuf nucleus has been identified in the cat, dog, and human. SYN: nucleus of pudendal nerve [TA]. [Onufrowicz, Wladislaus, Swiss anatomist.]
