daltonism

n. color-blindness (especially the inability to distinguish between red and green colors)

Color blindness, or color vision deficiency, in humans is the inability to perceive differences between some or all colors that other people can distinguish. It is most often of genetic nature, but may also occur because of eye, nerve, or brain damage, or due to exposure to certain chemicals. The English chemist John Dalton in 1798 published the first scientific paper on the subject, "Extraordinary facts relating to the vision of colours", after the realization of his own color blindness; because of Dalton's work, the condition is sometimes called Daltonism, although this term is now used for a type of color blindness called deuteranopia.
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Dal·ton·ism n. An inherited defect in the perception of red and green; red-green colorblindness. [more]Daltonism - Community and Resources

Noun
1. dichromacy characterized by a lowered sensitivity to green light resulting in an inability to distinguish green and purplish-red
(synonym) deuteranopia, green-blindness
(hypernym) red-green dichromacy, red-green color blindness, red-green colour blindness

(n.)
Inability to perceive or distinguish certain colors, esp. red; color blindness. It has various forms and degrees. So called from the chemist Dalton, who had this infirmity.