The placement of one's face, specifically the mouth, between the ass-cheeks of another person, followed by a rapid shaking of the face in a side-to-side motion accompanied by yelling. The resulting sound that is created sounds similar to an outboard boat motor.
-I'm into some pretty weird stuff, but mud boating isn't one of them.
-Cane: I'm going to get intimate with your sister...
Josh: After you mud boat me mother fucker!!
-She so fine, I'd mud boat the shit outta that bitch!