The Collaborative International Dictionary of English v.0.48:

deflower \de*flow"er\, v. t. [Previously also spelled
   deflour.] [imp. & p. p. Deflowered; p. pr. & vb. n.
   Deflowering.] [F. d['e]florer, LL. deflorare; L. de- +
   flos, floris, flower. See Flower, and cf. Deflorate.]
   1. To deprive of flowers.
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            An earthquake . . . deflowering the gardens. --W.
                                                  Montagu.
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   2. To take away the prime beauty and grace of; to rob of the
      choicest ornament.
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   3. To deprive of virginity, as a woman; to violate; to
      ravish; also, to seduce.
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            If a man had deflowered a virgin.     --Milton.
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WordNet (r) 3.0 (2006):

deflower
    v 1: deprive of virginity; "This dirty old man deflowered
         several young girls in the village" [syn: deflower,
         ruin]
    2: make imperfect; "nothing marred her beauty" [syn: mar,
       impair, spoil, deflower, vitiate]