A contest with two people consisting of many lame yo-mama jokes fired at each other at rapid speeds. The usual audiences of these are white, wanna-be gangsters who have failing socail skills.
White wanna-be: Dude, that yomamathon the other day was awesome!
Other guy: No, it was actually one of the worst oral experiences ever to pierce my ears.
by Mr. Whitey November 4, 2009
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