A Babylonian halakist of the third generation of Amoraim. He once visited Palestine, where he attended the lectures of Rab Assi (Yasa I.), and seems to have met Rabbi Johanan. He was a disciple of Rab Ḥisda in Babylonia, and appears frequently in controversy with Rab Ashi I. (Pes. 33b; Yeb. 117a; B. B. 3a, 46b, 56a; Ḥul. 31a, 50b).