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!!
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