A congenital deformity in which the buttocks can open up like the shells of a clam, with anus inside as a clam would be inside clamshells.
He dropped his shorts and then made everyone in the locker-room pass out from the sight of his clamshell anus.
by wiginpen February 15, 2004
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.Buy the mug