The act of being completely naked while thrusting so hard that your balls sack starts smacking against your taint hard enough to make a clapping sound. It is quite and impressive party trick might I add.
Yesterday, my mom caught me doing the sack clack and she started to join in and she was really good at it!
by RkoIsLife1738 December 1, 2016
Get the Sack Clackmug.