sneaker vs stoolpigeon

sneaker and stoolpigeon both are nouns.

Word	Noun	Adjective	Verb	Adverb
sneaker	Yes	No	No	No
stoolpigeon	Yes	No	No	No

As nouns, sneaker and stoolpigeon are synonyms defined as:

sneaker and stoolpigeon: someone acting as an informer or decoy for the police

Other synonyms of sneaker include canary, fink, sneak, snitch, snitcher, stool pigeon, stoolie.

sneaker (noun)	stoolpigeon (noun)
a canvas shoe with a pliable rubber sole	someone acting as an informer or decoy for the police
someone acting as an informer or decoy for the police