The Collaborative International Dictionary of English v.0.48:

Appetite \Ap"pe*tite\, n. [OE. appetit, F. app['e]tit, fr. L.
   appetitus, fr. appetere to strive after, long for; ad +
   petere to seek. See Petition, and cf. Appetence.]
   1. The desire for some personal gratification, either of the
      body or of the mind.
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            The object of appetite it whatsoever sensible good
            may be wished for; the object of will is that good
            which reason does lead us to seek.    --Hooker.
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   2. Desire for, or relish of, food or drink; hunger.
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            Men must have appetite before they will eat.
                                                  --Buckle.
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   3. Any strong desire; an eagerness or longing.
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            It God had given to eagles an appetite to swim.
                                                  --Jer. Taylor.
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            To gratify the vulgar appetite for the marvelous.
                                                  --Macaulay.
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   4. Tendency; appetency. [Obs.]
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            In all bodies there as an appetite of union.
                                                  --Bacon.
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   5. The thing desired. [Obs.]
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            Power being the natural appetite of princes.
                                                  --Swift.
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   Note: In old authors, appetite is followed by to or of, but
         regularly it should be followed by for before the
         object; as, an appetite for pleasure.
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   Syn: Craving; longing; desire; appetency; passion.
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WordNet (r) 3.0 (2006):

appetite
    n 1: a feeling of craving something; "an appetite for life";
         "the object of life is to satisfy as many appetencies as
         possible"- Granville Hicks [syn: appetite, appetency,
         appetence]

The Devil's Dictionary (1881-1906):

APPETITE, n.  An instinct thoughtfully implanted by Providence as a
solution to the labor question.