Occurs when the tail-end of a substantial turd (i.e. a turd the size of a zucchini or larger) whips the back of your balls while you're sitting on the can.
Generally, the physics of a shit whip require that the head of the turd first makes contact with the bottom of the bowl, thus providing the turd with the necessary leverage to allow for a slow, frontward collapse. If the cosmos are aligned just right, the motion will carry the tail-end of the turd forward and it will whip the back of your balls on the way down.
"Dude, I just got shit whipped."
The act of falling in such a way that you get instant whiplash on your way down and your face surges forward to meet the ground.
Robert fell of of his skateboard while grinding and got Shit whipped.