Strictly the ruler over the fourth part of a province; but the word denotes a ruler of a province generally ( Matthew 14:1 ; Luke 3:1,19 ; 9:7 ; Acts 13:1 ). Herod and Phasael, the sons of Antipater, were the first tetrarchs in Palestine. Herod the tetrarch had the title of king ( Matthew 14:9 ).
Source
- part_of
source-manifest/easton— Easton's Bible Dictionary (PD)