(Ἰωνικός), a physician of Sardis in Lydia, whose father had also followed the same profession with credit. He studied medicine under Zenon, and was a fellow-pupil of Oribasius and Magnus, in the latter half of the fourth century after Christ. Eunapius, who has given a short account of his life (De Vit. Philos. p. 174, ed. Antwerp.), says that he was not only well skilled in all the branches of medical science, but that he had also paid attention to rhetoric, logic, and poetry, and enjoyed the highest reputation.