Term: Color Temperature

The temperature of a color within its hue, either warm (towards red) or cool (towards blue). The only exception being a warm red which is towards orange, and cool blue which is towards green.

Color temperature should not be confused with the terms "warm colors", which are those in the yellow to red range (sometimes referred to as aggressive colors), and "cool colors", which are greens, blues, and violets and mixtures thereof.

"Hues which approach red have almost universally been considered as warm colors and those which tend toward blue as cool. Fire and sunlight and the glow of brisk circulation of blood are all associated with warmth. The colors of the sky and the distant mountains and cool waters are generally bluish. When the body is chilled its color trends toward a bluish hue. These reasons naturally make us associate red, orange, and yellow with warmth, and blue, blue-green and blue-violet with coolness." (Walter Sargeant, The Enjoyment and Use of Color)