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1.
the small flap of skin connecting the upper gum to the inside of the upper lip in the middle. May only be referred to as a mouth clit if the flap of skin is prominent in a person's smile.
Dude, have you seen the little nub under emily's lip when she smiles?
Yeah dude, that's her mouth clit.
by WHEEEEEEEEEEEEEW April 16, 2011