The act of losing your mind/going off for some reason. Similar to going berserk, only more filthy language is used etc. People most commonly go beresk when losing money through betting.
Person 1: I baced number 3 here.

Person 2: I backed number 2.

Race Caller: And number 2 misses the start horribly and cannot win!

Person 2: For fuck sake, EVERY FUCKING TIME i back something the motherfucking piece of filth makes me do my ass. For once in my fucking life can i please back a fucking winner for fuck sake!

Person 1: Mate, you've gone beresk..
by bereskhuman September 28, 2010
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