Maimonides calls them In Chullin 92a, Rav Yehuda uses the term tzadikei umos ha-olam'''צדיקי אומות העולם''' meaning '''Righteous of the Nations''', in his interpretation of Zecharia 11:13. Rav Yochanan in the name of Rav Shimon Ben Yehotzadak, however, says that it refers to the righteous of Israel. See Maharsha and Rashi with the Hagahos HaBach.