blabber vs nark

blabber and nark both are nouns.

Word	Noun	Adjective	Verb	Adverb
blabber	Yes	No	Yes	No
nark	Yes	No	Yes	No

As nouns, nark is a hyponym of blabber; that is, nark is a word with a more specific, narrower meaning than blabber:

blabber: one who reveals confidential information to the police or other authority
nark: an informer or spy working for the police

blabber (noun)	nark (noun)
one who reveals confidential information to the police or other authority	an informer or spy working for the police
	a lawman concerned with narcotics violations

blabber (verb)	nark (verb)
speak (about unimportant matters) rapidly and incessantly	inform or spy (for the police)
	cause annoyance in; disturb, especially by minor irritations