Young-Helmholtz theory of color vision
The theory that there are three sets of color-perceiving elements in the retina, red, green, and violet. Perception of the other colors arises from the combined stimulation of these elements.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.