Butt-yak
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!
Yak Butt
Someone with a large ass approximately the size of a Yak.
Dude, that ckicks Yak Butt almost tuched me.