To be very good at a game, to beast it. Either sport related or video games.

Originated from a misunderstanding of a name and stuck.
Guy1:did you see that dude uberpwn?!
Guy2:yea that was totally addimus fo sho.

Guy1:did he just dunk over that 7foot guy?
Guy2:addimus
by A Jiggins February 29, 2008
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