Commodore

1. (rank) Prior to 1997, the title was used in the Royal Navy for an officer of the rank of captain who was given temporary command of a squadron. At the end of the deployment of the squadron, or in the presence of an admiral, he would revert to his de facto rank of captain.
2. (rank) A military rank used in many navies that is superior to a navy captain but below a rear admiral. Often equivalent to the rank of "flotilla admiral" or sometimes "counter admiral" in non-English-speaking navies.
3. (convoy commodore) A civilian put in charge of the good order of the merchant ships in British convoys during World War II, but with no authority over naval ships escorting the convoy.
4. (commodore (yacht club)) An officer of a yacht club.
5. (Commodore (Sea Scouts)) A position in the Boy Scouts of America's Sea Scouts program.