Commodore

"Commodore" (Junsho) is a military rank used in some navies for officers whose position exceeds that of a Captain, but is less than that of an admiral. It is sometimes abbreviated as Cdre or COMO.

In One Piece a Commodore is the highest known rank below Rear Admiral.

The Rank is one being the least used in One Piece, being shown only twice so far. Its first representative, Purin-Purin, was, however, killed only a few panels after his appearance and the second holder, Smoker, was promoted to that rank during the course of the series (and also obtained it for a deed he did not do, yet he resisted this promotion as far as possible).

List of Commodores:
 * Purin Purin (deceased)
 * Nelson (Deceased)
 * Smoker

Note: One could point out that it was used thrice in the anime, yet the filler arc presented a Marine, Commodore Nelson, having the rank of "teitoku", which translates to Commodore, but which is not present in Oda's manga.