look up any word, like blumpkin:
 
2.
Break upp-abble offense
She farted in the middle of having sex. That was a total B.U.O.
by dango fett August 25, 2005
 
1.
Bruises of unknown origan
ie) After a night out drinking with friends I woke up with several b.u.o's.
by spiceS June 19, 2011