(n)dichromacy characterized by a lowered sensitivity to green light resulting in an inability to distinguish green and purplish-red, Syn.Daltonism, green-blindness
The Collaborative International Dictionary of English (GCIDE) v.0.53Collaborative International Dictionary (GCIDE)
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. Nichol. [ 1913 Webster ]