The Collaborative International Dictionary of English v.0.48:

Femininity \Fem`i*nin"i*ty\, n.
   1. The quality or nature of the female sex; womanliness.
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   2. The female form. [Obs.]
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            O serpent under femininitee.          --Chaucer.
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WordNet (r) 3.0 (2006):

femininity
    n 1: the trait of behaving in ways considered typical for women
         [syn: femininity, muliebrity] [ant: masculinity]