rankle vs rag

rankle is not a noun while rag is a noun.

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

As verbs, rag is a hypernym of rankle; that is, rag is a word with a broader meaning than rankle:

Other hypernyms of rankle include annoy, bother, chafe, devil, get at, get to, gravel, irritate, nark, nettle, rile, vex.

rankle (noun)	rag (noun)
	a boisterous practical joke (especially by college students)
	a small piece of cloth
	newspaper with half-size pages
	music with a syncopated melody (usually for the piano)
	a week at British universities during which side-shows and processions of floats are organized to raise money for charities

rankle (verb)	rag (verb)
gnaw into; make resentful or angry	break into lumps before sorting
	censure severely or angrily
	harass with persistent criticism or carping
	play in ragtime
	treat cruelly
	cause annoyance in; disturb, especially by minor irritations