Source : Webster's Revised Unabridged Dictionary (1913)

Polychromatic \Pol`y*chro*mat"ic\, a. [Poly- + chromatic.]
   Showing a variety, or a change, of colors.

   {Polychromatic acid} (Old Chem.), a substance obtained by the
      action of nitric acid on aloes.

Source : WordNet®

polychromatic
     adj 1: (of light or other electromagnetic radiation) composed of
            more than one wavelength; "polychromatic light" [ant:
            {monochromatic}]
     2: having or exhibiting many colors [syn: {polychrome}, {polychromic}]