grating vs cacophonous

grating is a noun but cacophonous is not a noun.

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

grating (noun)	cacophonous (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

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