To make ones butt cheaks clap together. It's a new phenomena which can mostly only be done by a chick wit a big ass. It's accomplished by abruptly bouncin dat ass but, like I said it's almost impossible unless you got a whole lotta ass.
an action wich usually happens during the act of intercorse. the clap is caused by the mans pelvis rapidly contacting the butox of their partner in such a way that it causes a claping sound.