The Greek term te·tra·arʹkhes literally means “ruler over one fourth”—that is, a quarter of a district, or province.

The tetrarchs, or district rulers, mentioned in the Bible are Herod Antipas, ruler of Galilee and Perea; his brother Philip, ruler of Ituraea and Trachonitis; and Lysanias, ruler of Abilene, all of whom ruled over a certain area designated by and subject to the authority of Rome. (Lu 3:1) Herod Antipas’ official Roman title was “tetrarch,” but he was popularly referred to as “king,” perhaps as a courtesy.—See study notes on Mt 14:1, 9; Mr 6:14; Lu 3:1.