cacophonic vs grating

cacophonic is not a noun while grating is a noun.

Word	Noun	Adjective	Verb	Adverb
cacophonic	No	Yes	No	No
grating	Yes	Yes	No	No

cacophonic (noun)	grating (noun)
	a barrier that has parallel or crossed bars blocking a passage but admitting air
	a frame of iron bars to hold a fire
	optical device consisting of a surface with many parallel grooves in it; disperses a beam of light (or other electromagnetic radiation) into its wavelengths to produce its spectrum

cacophonic (adjective)	grating (adjective)
having an unpleasant sound	unpleasantly harsh or grating in sound