The Collaborative International Dictionary of English v.0.48:

Daltonism \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.
   --Nichol.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Daltonism
    n 1: dichromacy characterized by a lowered sensitivity to green
         light resulting in an inability to distinguish green and
         purplish-red [syn: deuteranopia, Daltonism, green-
         blindness]