Noun. The act of rubbing the knuckles of one or both hands on ones bootyhole and then proceeding to punch another individual with said hand(s).
"Bro, Jimmy fucked my wife so I had to hit him with that brown knuck. Gave that bastard a black eye and pink eye at the same time."

"Your father would be proud, John."

"Thanks Mom."
by The Hon. Dr. Rev. Smokaspliff December 13, 2021
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