dichromatism

noun

1. the quality or state of being dichromatic.
2. Also called di·chro·ma·top·si·a [dahy-kroh-muh-top-see-uh] /daɪˌkroʊ məˈtɒp si ə/. Ophthalmology. a defect of vision in which the retina responds to only two of the three primary colors.Compare monochromatism(def 2), trichromatism(def 3).

n.

1. The state of being dichromatic.
2. A form of colorblindness in which only two of the three fundamental colors can be distinguished due to a lack of one of the retinal cone pigments.dichromatopsia dyschromatopsia parachromatopsia