monochromatic vs monochrome

monochromatic is not a noun while monochrome is a noun.

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

As adjectives, monochromatic and monochrome are synonyms defined as:

monochromatic and monochrome: having or appearing to have only one color

Other synonyms of monochromatic include monochromic, monochromous.

monochromatic (noun)	monochrome (noun)
	a black-and-white photograph or slide
	painting done in a range of tones of a single color

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