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1 definition by Poor Child

A way to signify someone screwing up, or failing miserably.

Made famous by the 11 year old Youtube trainwreck "Jessi Slaughter" aka "kerligirl13" and her Father.
Your daughter is posting nudes on the internet.... ya dun goofed.

All ya haters aint got nothin on me, ya dun goofed, I'ma make a brain slushie.
by Poor Child July 15, 2010