Dal·ton·ism /-ṇˌɪzəm/ 名詞
Dal·ton·ism 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.
n : dichromacy characterized by a lowered sensitivity to green
light resulting in an inability to distinguish green and
purplish-red [syn: deuteranopia, green-blindness]