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1 definition by Kevin Kugler

 
1.

A form of measurement used to determine the size or width of a vagina or anus, or the act of inserting fingers into said orifices. Preceded by a number which indicates how many knuckles.

---It still has not been determined if fisting someone is considered 4 or 5 knuckles deep, as the debate contiunes if the thumb counts as a knuckle
"So last night I was two knuckles deep in this chick's ass..."

"Her pussy was three knuckles deep--pretty impressive."
by Kevin Kugler March 01, 2006