The act of shitting in the pocket your hand. Followed by you slapping the face of your partner making it look like they've been slapped by a cave man with filthy hands.
"Tilly was extremely upset about the Caveman Slap she had recieved hours earlier because it still smelt horrid."

"Cletus suffered severe cramps from laughing so hard after he slapped Tilly in the face with a handfull of shit, caveman slap style."
by Dal-Dal October 11, 2006
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