The answer is "Talmud".
Hillel and Shammai were two Rabbis of the first common era, house of Hillel and house of Shammai. “Talmud" deciphers truly as "instruction" in Hebrew, and the term may allude to either the Gemara alone, or the Mishnah and Gemara together. The Talmud is the reason for all codes of Jewish law, and is generally cited in rabbinic writing, got from the debate between Hillel and Shammai that set the tone of controversy and exchange that is characteristic for Talmudic Judaism.