Commander /(?)/

Com·mand·er

Commander

n.
  1. A chief; one who has supreme authority; a leader; the chief officer of an army, or of any division of it.
    A leader and commander to the people.
    — Is. lv. 4.
  2. An officer who ranks next below a captain, -- ranking with a lieutenant colonel in the army. (Navy)
  3. The chief officer of a commandery.
  4. A heavy beetle or wooden mallet, used in paving, in sail lofts, etc.

Phrases & Compounds
Commander in chief
the military title of the officer who has supreme command of the land or naval forces or the united forces of a nation or state; a generalissimo. The President is commander in chief of the army and navy of the United States.