Source : Webster's Revised Unabridged Dictionary (1913)

Decolor \De*col"or\, v. t. [Cf. F. d['e]colorer, L. decolorare.
   Cf. {Discolor}.]
   To deprive of color; to bleach.

Source : WordNet®

decolor
     v : remove color from; "The sun bleached the red shirt" [syn: {bleach},
          {bleach out}, {decolour}, {decolorize}, {decolourize}, {decolorise},
          {decolourise}, {discolorize}, {discolourise}, {discolorise}]