The Collaborative International Dictionary of English v.0.48:

Wither \With"er\, v. i. [imp. & p. p. Withered; p. pr. & vb.
   n. Withering.] [OE. wideren; probably the same word as
   wederen to weather (see Weather, v. & n.); or cf. G.
   verwittern to decay, to be weather-beaten, Lith. vysti to
   wither.]
   [1913 Webster]
   1. To fade; to lose freshness; to become sapless; to become
      sapless; to dry or shrivel up.
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            Shall he hot pull up the roots thereof, and cut off
            the fruit thereof, that it wither?    --Ezek. xvii.
                                                  9.
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   2. To lose or want animal moisture; to waste; to pin? away,
      as animal bodies.
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            This is man, old, wrinkled, faded, withered. --Shak.
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            There was a man which had his hand withered. --Matt.
                                                  xii. 10.
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            Now warm in love, now with'ring in the grave.
                                                  --Dryden.
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   3. To lose vigor or power; to languish; to pass away. "Names
      that must not wither." --Byron.
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            States thrive or wither as moons wax and wane.
                                                  --Cowper.
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The Collaborative International Dictionary of English v.0.48:

Wither \With"er\, v. t.
   1. To cause to fade, and become dry.
      [1913 Webster]

            The sun is no sooner risen with a burning heat, but
            it withereth the grass, and the flower thereof
            falleth.                              --James i. 11.
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   2. To cause to shrink, wrinkle, or decay, for want of animal
      moisture. "Age can not wither her." --Shak.
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            Shot forth pernicious fire
            Among the accursed, that withered all their
            strength.                             --Milton.
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   3. To cause to languish, perish, or pass away; to blight; as,
      a reputation withered by calumny.
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            The passions and the cares that wither life.
                                                  --Bryant.
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WordNet (r) 3.0 (2006):

wither
    v 1: wither, as with a loss of moisture; "The fruit dried and
         shriveled" [syn: shrivel, shrivel up, shrink,
         wither]
    2: lose freshness, vigor, or vitality; "Her bloom was fading"
       [syn: fade, wither]