rankle vs grate

rankle is not a noun while grate is a noun.

Word	Noun	Adjective	Verb	Adverb
rankle	No	No	Yes	No
grate	Yes	No	Yes	No

As verbs, rankle and grate are synonyms defined as:

Other synonyms of rankle include eat into, fret.

rankle (noun)	grate (noun)
	a frame of iron bars to hold a fire
	a barrier that has parallel or crossed bars blocking a passage but admitting air
	a harsh rasping sound made by scraping something

rankle (verb)	grate (verb)
gnaw into; make resentful or angry	make a grating or grinding sound by rubbing together
	scratch repeatedly
	reduce to small shreds or pulverize by rubbing against a rough or sharp perforated surface
	gnaw into; make resentful or angry
	furnish with a grate