When the lady lies on her stomach with back arched and the gentleman sits on her shoulders with the head of a turd sticking out (see turtle head). He then procedes to slide down her back with the aid of the turd.
"I built up so much speed giving her a mudslide the other night that I got whiplash."
A type of bong that the head piece(where the weed goes) is used as the carb of the bong. When the bong is full of smoke u pull the head piece off and inhale.