Commodore

Commodore is a naval rank, the equivalent of which is used by the service organizations of many civilizations. As a traditional grade, commodore is the most junior flag officer rank of a naval organization, under an admiral rank (usually under Rear Admiral) but senior to a Captain. Commodores command groups of ships, as opposed to Captains commanding single ships or units. In comparison to other ranking systems, this rank is equivalent to the military Brigadier or Brigadier General.

Many rank systems only use this rank during wartime, during times of peace an officer of this rank is refered to as a 'Rear Admiral - Lower Half.'

The rank of Commodore was used by starfleet until at least the 2270's.


 * The rank of 'Commodore' appears to have been superceded by the 24th century, as no such ranked persons were seen or referenced in TNG, DS9 or VOY.

From Memory Alpha -- the free Star Trek reference

Star Trek: Intrepid
As of the 2380s, the rank of Commodore was still in use by some officers, albeit in a much more limited area than its counterpart, Rear Admiral. Aaron Prentice was an example of one such officer.