Greek Talmudist of the eleventh and twelfth centuries. He was a pupil of Rashi, and is mentioned by Mordecai b. Hillel (Haggahot on Giṭ. No. 466). Hillel wrote a commentary to Sifra in which he often quotes Rashi and Isaac b. Melchizedek; he also wrote a commentary to Sifre. Both works were known to the tosafists; the former is mentioned in the "Sefer Yiḥuse ha-Tanna'im weha-Amora'im," the latter in the Tosefta (Soṭah 15a, 38a) and in the Mordekai (Giṭ. No. 376). The former is also quoted by Elijah Mizraḥi in his commentary on Rashi, by Aaron b. Ḥayyim in his "Ḳorban Aharon," and by Menahem Azariah Fano in his Responsa (No. 11).