the son of Amminadab, the son of Aram, the son of Joram,{TR omits "the son of Joram"} the son of Hezron, the son of Perez, the son of Judah,
And the word "tetrarch" means a ruler of a fourth part. And when Herod the Great died, he left the ruling of that area, they divided it into four, and three of his sons ruled over a part of the area. So a tetrarch was a ruler of a fourth part, and Philip the tetrarch of Iturea, Herod the tetrarch of Galilee,