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Sin Chin: The abrasion a woman is left with after making out with some guy who didn't have the decency to shave his stubble therefore leaving her looking busted with a red-ass chin the next day.

me: "Yo, who you with last night!?"

skank: "Who? What?"

me: "You got sin chin bizzatch...tell that douche bag to shave next time!"
by Ho's R People 2 October 22, 2008
The word that refers to a condition where a person's chin resembles an anus. (Meaning it is split into two parts)
Look at that man's chin, its a sinchin, how disgusting!
by Vleis.van.den.Doos March 30, 2009
Another word for a double chin.

Look at the sinchin on that man's neck!
by Phil.123.Smith June 23, 2007