Trey is kind of a nickname-y name all by itself.
Famous people named Trey:
Actor/screenwriter Trey Parker III; sportscaster Trey Wingo III; U.S. Congressman Trey Gowdy III; rapper Trey Songz (born Tremaine Aldon Neverson); son of Will Smith, Trey Smith III.
In basketball, "trey" is also the slang term for a three-point shot.
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