trīˈkrōməˌtizəm noun
Etymology: trichromat ic + -ism
1. : the quality or state of being trichromatic : the use of three colors (as in photography)
2. also tri·chro·ma·cy -əsē -es : vision in which all of the fundamental colors are perceived though not necessarily with equal facility — compare dichromatism , monochromatism