1. A part of one's entourage, generally a male, known for their excessive use of "swoop," a tactic where one attempts to pick-up a female who is already clearly being macked on by one of their friends.
Male 1: "WTF?! That guy in the Spartan costume totally came in and started mackin' on the girl I was talking to!"
Male 2: "He's a total 'Swoop Dawg.' Actually, that's what we call him. You didn't know?"