color blindness [L, color; AS blint] , an abnormal condition characterized by an inability to distinguish colors of the spectrum clearly. In most cases it is not a blindness but a weakness in perceiving colors distinctly. There are two forms of color blindness: Daltonism, the more common form, is characterized by an inability to distinguish reds from greens. It is an inherited, sex-linked disorder. Total color blindness, or achromatic vision, is characterized by an inability to perceive any color at all. Only white, gray, and black are seen. It may be the result of a defect in or absence of the cones in the retina. Also spelled colour blindness.
