The Collaborative International Dictionary of English v.0.48:

Gentility \Gen*til"i*ty\, n. [L. gentilitas the relationship of
   those who belong to the same clan, also, heathenism: cf. F.
   gentilit['e] heathenism. See Gentile.]
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   1. Good extraction; dignity of birth. --Macaulay.
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            He . . . mines my gentility with my education.
                                                  --Shak.
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   2. The quality or qualities appropriate to those who are well
      born, as self-respect, dignity, courage, courtesy,
      politeness of manner, a graceful and easy mien and
      behavior, etc.; good breeding.
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   3. The class in society who are, or are expected to be,
      genteel; the gentry. [R.] --Sir J. Davies.
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   4. Paganism; heathenism. [Obs.] --Hooker.
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WordNet (r) 3.0 (2006):

gentility
    n 1: elegance by virtue of fineness of manner and expression
         [syn: breeding, genteelness, gentility]