supergrass vs squealer

supergrass and squealer both are nouns.

Word	Noun	Adjective	Verb	Adverb
supergrass	Yes	No	No	No
squealer	Yes	No	No	No

As nouns, squealer is a hypernym of supergrass; that is, squealer is a word with a broader meaning than supergrass:

supergrass: a police informer who implicates many people
squealer: one who reveals confidential information to the police or other authority

Other hypernyms of supergrass include betrayer, blabber, informer, rat.

supergrass (noun)	squealer (noun)
a police informer who implicates many people	domestic swine
	one who reveals confidential information to the police or other authority