monochromacy vs monochromatic vision

monochromacy and monochromatic vision both are nouns.

Word	Noun	Adjective	Verb	Adverb
monochromacy	Yes	No	No	No
monochromatic vision	Yes	No	No	No

As nouns, monochromacy and monochromatic vision are synonyms defined as:

monochromacy and monochromatic vision: complete color blindness; colors can be differentiated only on the basis of brightness

Other synonyms of monochromacy include monochromasy, monochromatism, monochromia.

monochromacy (noun)	monochromatic vision (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