High Quality Content by WIKIPEDIA articles! A flag officer is a commissioned officer in a nation`s armed forces senior enough to be entitled to fly a flag to mark where the officer exercises command. The term usually refers to the senior officers in an English-speaking nation`s navy, specifically those who hold any of the admiral ranks; in some cases it applies also to those holding the rank of commodore. In U.S. usage it is additionally applied to general officers in the Army, Air Force, Marine Corps, and Coast Guard entitled to fly their own flags.