Source : Webster's Revised Unabridged Dictionary (1913)

Monochromic \Mon`o*chro"mic\, a.
   Made, or done, with a single color; as, a monochromic
   picture.

Source : WordNet®

monochromic
     adj : having or appearing to have only one color [syn: {monochromatic},
            {monochrome}, {monochromous}]