monochromatic vs monochromatism

monochromatic is not a noun while monochromatism is a noun.

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

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

monochromatic (adjective)	monochromatism (adjective)
(of light or other electromagnetic radiation) having only one wavelength
of or relating to monochromatism
having or appearing to have only one color