a stool pigeon

a person, especially a criminal, who secretly gives information to the police in order to help them catch other criminals Once they discovered he was a stool pigeon, it was only a matter of time before they had him killed.

Common Names:

Name	Pronounced	Usage
Scotty	-	English, Scottish
Jimeno	hee-ME-no	Spanish (Rare)
Hani	-	Arabic
Tiede	TEE-də (Dutch)	Frisian, Dutch
Chappell	[tʃæpəl]
Rudo	-	Southern African, Shona