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 rank.
3. An officer in some knightly or fraternal orders.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.