D defs.my
Entry 4 senses Webster, 1913

Commodore

/käm'-əd-ôrˌ/ · Com·mo·dore · IPA /ˈkɑ.mə.dɔɹ/
01 n. An officer who ranks next above a captain; sometimes, by courtesy, the senior captain of a squadron. The rank of commodore corresponds with…
  1. 1.
    An officer who ranks next above a captain; sometimes, by courtesy, the senior captain of a squadron. The rank of commodore corresponds with that of brigadier general in the army.(U. S. Navy)
  2. 2.
    A captain commanding a squadron, or a division of a fleet, or having the temporary rank of rear admiral.(British Navy)
  3. 3.
    A title given by courtesy to the senior captain of a line of merchant vessels, and also to the chief officer of a yachting or rowing club.
  4. 4.
    A familiar for the flagship, or for the principal vessel of a squadron or fleet.