Monochromatism: 1) Total inability to perceive color. A person with true monochromatism perceives only black, white, and shades of gray. It is due to lack of or damage to the cones of the eye that perceive color, or to inability of the nerves to translate information received from the cones. Complete monochromatism is usually an inherited condition. 2) One of the many types of colorblindness that affects perception of certain colors only.