Source : Webster's Revised Unabridged Dictionary (1913)

Chromatic \Chro*mat"ic\, a. [L. chromaticus, Gr. ?, suited for
   color, fr. ?, ?, color; akin to ? color, ? skin, color of the
   skin.]
   1. Relating to color, or to colors.

   2. (Mus.) Proceeding by the smaller intervals (half steps or
      semitones) of the scale, instead of the regular intervals
      of the diatonic scale.

   Note: The intermediate tones were formerly written and
         printed in colors.

   {Chromatic aberration}. (Opt.) See {Aberration}, {4}.

   {Chromatic printing}, printing from type or blocks covered
      with inks of various colors.

   {Chromatic scale} (Mus.), the scale consisting of thirteen
      tones, including the eight scale tones and the five
      intermediate tones.

Source : WordNet®

chromatic
     adj 1: able to refract light without spectral color separation;
            "chromatic lens"
     2: based on a scale consisting of 12 semitones; "a chromatic
        scale" [ant: {diatonic}]
     3: being or having or characterized by hue [ant: {achromatic}]