Pronunciation: (kom'u-dôr", -dōr"),[key] —n. 1. Navy.a grade of flag officer next in rank below a rear admiral.
2. Brit. Navy.an officer in temporary command of a squadron, sometimes over a captain on the same ship.
3. Navy.the senior captain when two or more ships of war are cruising in company.
4. (in the U.S. Navy and Merchant Marine) the officer in command of a convoy.
5. the senior captain of a line of merchant vessels.
6. the president or head of a yacht club or boat club.