a. one of a pair of primary or secondary colors opposed to the other member of the pair on a schematic chart or scale (color wheel), as green opposed to red, orange opposed to blue, or violet opposed to yellow.
b. the relationship of these pairs of colors perceived as completing or enhancing each other.
2. See secondary color.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.