Geonim (Hebrew: גְאוֹנִים, lit. 'Excellencies', [ɡe(ʔ)oˈnim]; also transliterated as Gaonim; sing. Gaon, גָאוֹן, 'Excellency') were the chiefs of the Sura and Pumedita Academies, the two great Talmudic Academies in Babylonia during the Abbasid Caliphate. They were generally accepted as the spiritual leaders of the Jewish community worldwide in the Early Middle Ages, in contrast to the Resh Galuta (Jewish Babylonian Aramaic: רֵישׁ גָּלוּתָא, lit. 'Head [of the] Exile') who wielded secular authority over the Jews in Islamic lands.
The title is derived from gei'on (גְאוֹן, 'pride' or 'majesty'), a Biblical Hebrew term found in Psalm 47:5, Nahum 2:3, Amos 6:8, and Amos 8:7, among other texts of the Hebrew Bible. In Modern Hebrew, the term (גאון) translates to "genius". The Geonim played a prominent and decisive role in the transmission and teaching of Torah and Halakha (Jewish law). They taught and studied Talmud and were decisors on halakhic matters regarding which no judgments had previously been rendered.