The Collaborative International Dictionary of English v.0.48:

nymph \nymph\ (n[i^]mf), n. [L. nympha nymph, bride, young
   woman, Gr. ny`mfh: cf. F. nymphe. Cf. Nuptial.]
   [1913 Webster]
   1. (Class. Myth.) A goddess of the mountains, forests,
      meadows, or waters.
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            Where were ye, nymphs, when the remorseless deep
            Closed o'er the head of your loved Lycidas?
                                                  --Milton.
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   2. Hence: A lovely young girl; a maiden; a damsel.
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            Nymph, in thy orisons
            Be all my sins remembered.            --Shak.
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   3. (Zool.) The pupa of an insect; a chrysalis.
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   4. (Zool.) Any one of a subfamily (Najades) of butterflies
      including the purples, the fritillaries, the peacock
      butterfly, etc.; -- called also naiad.
      [1913 Webster]

WordNet (r) 3.0 (2006):

nymph
    n 1: (classical mythology) a minor nature goddess usually
         depicted as a beautiful maiden; "the ancient Greeks
         believed that nymphs inhabited forests and bodies of water"
    2: a larva of an insect with incomplete metamorphosis (as the
       dragonfly or mayfly)
    3: a voluptuously beautiful young woman [syn: nymph, houri]