monochrome vs monochromatic

monochrome is a noun but monochromatic is not a noun.

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

As adjectives, monochrome and monochromatic are synonyms defined as:

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

Other synonyms of monochrome include monochromic, monochromous.

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

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