A big fatlarge ass found on American women that arises from spending way too much time eating at McDonalds. The kind of booty that hangs over the side of the bench as she is shoving down another quater-pounder with cheese.
OMFG that white women's McButt is hanging so low it touches the floor.
by MoneyG March 28, 2004
The term for a sexual act whereby one participant places their anus on the mouth of another participant, thereby resulting in the immediate ejaculation of the receiver.
Man, I jizzed a few seconds after she sat on my face so I guess that doesn't count as a McButt.
by funkybuttlovin June 23, 2014