The Collaborative International Dictionary of English v.0.48:

Humanity \Hu*man"i*ty\, n.; pl. Humanities. [L. humanitas: cf.
   F. humanit['e]. See Human.]
   1. The quality of being human; the peculiar nature of man, by
      which he is distinguished from other beings.
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   2. Mankind collectively; the human race.
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            But hearing oftentimes
            The still, and music humanity.        --Wordsworth.
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            It is a debt we owe to humanity.      --S. S. Smith.
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   3. The quality of being humane; the kind feelings,
      dispositions, and sympathies of man; especially, a
      disposition to relieve persons or animals in distress, and
      to treat all creatures with kindness and tenderness. "The
      common offices of humanity and friendship." --Locke.
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   4. Mental cultivation; liberal education; instruction in
      classical and polite literature.
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            Polished with humanity and the study of witty
            science.                              --Holland.
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   5. pl. (With definite article) The branches of polite or
      elegant learning; as language, rhetoric, poetry, and the
      ancient classics; belles-letters.
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   Note: The cultivation of the languages, literature, history,
         and arch[ae]ology of Greece and Rome, were very
         commonly called liter[ae] humaniores, or, in English,
         the humanities, . . . by way of opposition to the
         liter[ae] divin[ae], or divinity. --G. P. Marsh.
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WordNet (r) 3.0 (2006):

humanity
    n 1: the quality of being humane
    2: the quality of being human; "he feared the speedy decline of
       all manhood" [syn: humanness, humanity, manhood]
    3: all of the living human inhabitants of the earth; "all the
       world loves a lover"; "she always used `humankind' because
       `mankind' seemed to slight the women" [syn: world, human
       race, humanity, humankind, human beings, humans,
       mankind, man]

The Devil's Dictionary (1881-1906):

HUMANITY, n.  The human race, collectively, exclusive of the
anthropoid poets.