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!
When a woman takes a shit upside down and the shit lines the crack of her ass. And you fuck her using her shit as lube and then you paint each other's faces like deadpool with the shit