Someone with a large ass approximately the size of a Yak.
Dude, that ckicks Yak Butt almost tuched me.
by Kevin August 5, 2004
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VERB, An expulsion of flatus during a bowel movement that is powerful enough to throw a heavy spatter of semi-liquid feces in a muddy spraypaint fashion.
I butt-yakked so hard that I got some on the seat!
by The West Side Smasher April 25, 2003
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