monochromatism vs monochromia

monochromatism and monochromia both are nouns.

Word	Noun	Adjective	Verb	Adverb
monochromatism	Yes	No	No	No
monochromia	Yes	No	No	No

As nouns, monochromatism and monochromia are synonyms defined as:

monochromatism and monochromia: complete color blindness; colors can be differentiated only on the basis of brightness

Other synonyms of monochromatism include monochromacy, monochromasy, monochromatic vision.

monochromatism (noun)	monochromia (noun)
complete color blindness; colors can be differentiated only on the basis of brightness	complete color blindness; colors can be differentiated only on the basis of brightness