monochromic

from WordNet (r) 3.0 (2006)

monochromic
    adj 1: having or appearing to have only one color [syn:
           {monochromatic}, {monochrome}, {monochromic},
           {monochromous}]

from The Collaborative International Dictionary of English v.0.48

Monochromic \Mon`o*chro"mic\, a.
   Made, or done, with a single color; as, a monochromic
   picture. Called also, {monochromatic} and {monochrome}.
   [1913 Webster +PJC]