1. A person who commands, especially a commanding officer.
a. A commissioned rank in the US Navy or Coast Guard that is above lieutenant commander and below captain.
b. One who holds this rank or a similar rank in another military organization.
c. The chief commissioned officer of a military unit regardless of his or her rank.
3. An officer in some knightly or fraternal orders.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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