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1.
Thoin, n.: that really awkward area where the thigh ends and the groin begins. Often used as a meter of the appropriateness of clothing, i.e., shorts/skirts that show thigh are considered "appropriate"; shorts/skirts that show thoin are not.
Dude, those are really awkward holes in your jeans; I can see WAY too much thoin.
by maianess May 14, 2009