eat into vs nark

eat into is not a noun while nark is a noun.

Word	Noun	Adjective	Verb	Adverb
eat into	No	No	Yes	No
nark	Yes	No	Yes	No

As verbs, nark is a hypernym of eat into; that is, nark is a word with a broader meaning than eat into:

Other hypernyms of eat into include annoy, bother, chafe, devil, get at, get to, gravel, irritate, nettle, rag, rile, vex.

eat into (noun)	nark (noun)
	an informer or spy working for the police
	a lawman concerned with narcotics violations

eat into (verb)	nark (verb)
gnaw into; make resentful or angry	inform or spy (for the police)
	cause annoyance in; disturb, especially by minor irritations