ButtCussion: Severe fall landing directly on one's posterior axis, causing severe pain to the point of nausea - as in a "concussion of the butt." Falling and landing directly on the gluteus maximus or worse, a direct blow to the coccyx, with pain so severe that it causes concussion-like symptoms.
He jumped up into the air over the frozen swimming pool, cannonball-style with ass pointed down and knees up, thinking the ice would break and he would polar bear it but the ice did not break - Total Buttcussion!!
Ruler of Lake Titicaca. Rumored to have a bunghole that gets very angry if it does not receive toilet paper. Cornholio the Great is often seen walking around with his shirt over his head and his hands in the air, chanting songs about his power, and his bunghole.
"I am Cornholio! You do not want to face the wrath of my bunghole, for I need TP!"
Butthead: Shut up, Beavis! (uh huh huh huh)
Beavis: Um, okay. (heh heh heh heh).