The Collaborative International Dictionary of English v.0.48:

Discolor \Dis*col"or\, v. t. [imp. & p. p. Discolored; p. pr.
   & vb. n. Discoloring.] [OE. descolouren, OF. descolorer, F.
   d['e]colorer, fr. L. dis- + cololare, coloratum, to color,
   color color. See Color.] [Written also discolour.]
   1. To alter the natural hue or color of; to change to a
      different color; to stain; to tinge; as, a drop of wine
      will discolor water; silver is discolored by sea water.
      [1913 Webster]

   2. To alter the true complexion or appearance of; to put a
      false hue upon.
      [1913 Webster]

            To discolor all your ideas.           --Watts.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

discolored \dis*col"ored\, a.
   1. Altered in color; stained; spotted or streaked with
      foreign matter.

   Syn: discoloured. [1913 Webster]

   2. Variegated; of divers colors. [R.]
      [1913 Webster]

            That ever wore discolored arms.       --Chapman.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

71 Moby Thesaurus words for "discolored":
   achromatic, achromic, anemic, ashen, ashy, besmirched, blackened,
   bled white, bloodless, cadaverous, chloranemic, colorless,
   darkened, dead, deadly pale, deathly pale, dim, dimmed, dingy,
   dull, etiolated, exsanguinated, exsanguine, exsanguineous, faded,
   faint, fallow, flat, foxed, foxy, ghastly, gray, haggard, hueless,
   hypochromic, inky, lackluster, leaden, livid, lurid, lusterless,
   mat, mealy, muddy, murky, neutral, pale, pale as death, pale-faced,
   pallid, pasty, sallow, sickly, smirched, smoky, soiled, stained,
   stigmatic, stigmatiferous, stigmatized, tainted, tallow-faced,
   tarnished, toneless, uncolored, wan, washed-out, waxen, weak,
   whey-faced, white