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1.
The knuckle in which you use to barf with. Normally used by people who are anorexic or just need to blow chunks.
Dude One: "Man, have you seen that chicks barf knuckle?"
Dude Two: "Yeah man, she needs to tone it down, it is starting to callus"
Dude One: "Thats gross man."
by Lucid Samsara Phunkylove May 13, 2010