1. That aspect of things that is caused by differing qualities of the light reflected or emitted by them, definable in terms of the observer or of the light, as:

a. The appearance of objects or light sources described in terms of the individual’s perception of them, involving hue, lightness, and saturation for objects, and hue, brightness, and saturation for light sources.
b. The characteristics of light by which the individual is made aware of objects or light sources through the receptors of the eye, described in terms of dominant wavelength, luminance, and purity.
c. A gradation or variation of this aspect, especially when other than black, white, or gray; a hue: fireworks that exploded in brilliant colors.
2. A substance, such as a dye, pigment, or paint, that imparts a hue.


a. The use of different colors in visual representation.
b. The different colors used in visual representation