A '1337' way of expressing one's feelings about an unfavourable situation - most frequently used when someone is beaten, outdone or likewise. In full, it means 'Oh My God, you have used some sort of cheating mechanism to beat me'.

Originates from claiming that a computer gamer is winning by using a hack (see hax).
Person 1: I got 100% on my exam!
Person 2: Omg u hax!
by Rock DJ December 30, 2005
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The Best Low Level Pure In Runescape. Hes 1 Prayer and can still out tank anybody in a clan war.
DUDE! Did you see Omg U Hax Me tank all of them? And to think hes only 1 Prayer!
by Rick Mosses August 24, 2009
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