The Collaborative International Dictionary of English v.0.48:

Bleaching \Bleach"ing\, n.
   The act or process of whitening, by removing color or stains;
   esp. the process of whitening fabrics by chemical agents.
   --Ure.
   [1913 Webster]

   Bleaching powder, a powder for bleaching, consisting of
      chloride of lime, or some other chemical or chemicals.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bleach \Bleach\, v. t. [imp. & p. p. Bleached; p. pr. & vb. n.
   Bleaching.] [OE. blakien, blechen, v. t. & v. i., AS.
   bl[=a]cian, bl?can, to grow pale; akin to Icel. bleikja, Sw.
   bleka, Dan. blege, D. bleeken, G. bleichen, AS. bl[=a]c pale.
   See Bleak, a.]
   To make white, or whiter; to remove the color, or stains,
   from; to blanch; to whiten.
   [1913 Webster]

         The destruction of the coloring matters attached to the
         bodies to be bleached is effected either by the action
         of the air and light, of chlorine, or of sulphurous
         acid.                                    --Ure.
   [1913 Webster]

         Immortal liberty, whose look sublime
         Hath bleached the tyrant's cheek in every varying
         clime.                                   --Smollett.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "bleaching":
   achromatization, albification, blanching, bleach, decoloration,
   decolorization, decolorizing, discoloration, etiolation, fading,
   frosting, grizzling, lightening, madder bleach, market bleach,
   paling, silvering, whitening, whitewashing