- any ruler of a fourth part, division, etc.
- a subordinate ruler.
- one of four joint rulers or chiefs.
- the ruler of the fourth part of a country or province in the ancient Roman Empire.
- the ruler of one fourth of a country
- a subordinate ruler, esp of Syria under the Roman Empire
- the commander of one of the smaller subdivisions of a Macedonian phalanx
- any of four joint rulers
n.late Old English tetrarche “ruler of one of four divisions of a kingdom or province,” from Late Latin tetrarcha, from Greek tetrarkhes “leader of four companies, tetrarch,” from tetra- “four” (see tetra-) + arkhein “to rule” (see archon). Applied generally to subordinate rulers in the Roman Empire, especially in Syria.