In the video game Gears Of War, someone who picks up the sniper rifle, fires a round off to acheive an active reload, then downs someone as a coward would, leaving them for dead. They are liable for receiving an earful of trashtalk and slang pertaining to their mothers.
Active Noob: "OMG IM SO GOOD WITH SNIPER!!! I OWNED YOU ALL"

Player 1: "Wow, you actived-me-down you fucking active noob nice job go hang yourself with the cord on your xbox controller."
by Fat Girls Smell February 5, 2008
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