a terrible internet spelling of the classic "sassy black woman" statement of "Oh no, you didn't!!" Insert Finger snaps where appropriate. Commonly used in online forums and in online games i.e. Call Of Duty, Halo, /b/, Counter Strike, etc.
OhNoUddnt just fucking tea-bag my corpse AGAIN!!!

-or-

OHNOUDDNT just call me a newb, YOUR a fucking newb!!!

-or-

an enemy player is attempting to sneak up on your position, unaware he is displayed on your radar or UAV and you run around the corner and dump full auto into his face and exclaim "OHNOUDDNT!!"
by George F. Dorn September 20, 2009
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