Someone who plays Garry's Mod, and utilises the physics gun, therein to fling various 'props' (spawned items, used to build contraptions) at other players, killing them. This is usually frowned upon within Garry's Mod, as a prokiller is considered 'mingy'
Player 1: ADMIN! PLAYER 2 IS A PROPKILLER!
Player 2: I'm not a propkiller, Player 1 is lieing. *flings prop at Player 1*
Player 2: I'm not a propkiller, Player 1 is lieing. *flings prop at Player 1*
by Berberhb January 11, 2014
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