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A more aggressive version of fisting that results in g-spot or prostate contusions.
"Yo, bra, why's your hand in a cast?"
"I broke it knucklin' your mom last night."

-or-

"Why are you walking so messed up, were you riding a horse?"
"Naw man, I spent last night getting knuckled by 8 dudes and now my ass is broken like Angel's face from Fight Club."
by n@sty n8 d0gg January 23, 2009
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