Definition of "tetrarch" [te•trarch]

• A subordinate ruler. (noun)
• One of four joint rulers. (noun)
• A governor of one of four divisions of a country or province, especially in the ancient Roman Empire. (noun)
• The commander of a subdivision of a phalanx in ancient Greece. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The title tetrarch literally denotes one who rules over a fourth part of any country."
• "The word tetrarch properly denotes one who presides over a fourth part of a country or province; but it also came to be a general title, denoting one who reigned over any part -- a, third, a half, &c. In this case Herod had a third of the dominions of his father, but he was called tetrarch."
• "Herod Antipas is distinctively called the tetrarch in Matt."