di·chro·ma·tism (dī-krō

mə-tĭz

əm) also 
di·chro·mism (-mĭz

əm)
n.►  The quality or condition of being dichromatic.
►  Pathology. A form of colorblindness in which only two of the three fundamental colors can be distinguished due to a lack of one of the cone pigments. 
 [TahlilGaran] American Dictionary ▲