What is freedom from mixture or dilution with white; purity; -- said of colors. Note: The degree of saturation of a color is its relative purity, or freedom from admixture with white called?

saturation — (Optics) Freedom from mixture or dilution with white; purity; -- said of colors. Note: The degree of saturation of a color is its relative purity, or freedom from admixture with white. (Webster's 1913.)

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