a rat fink

(American informal)

an extremely unpleasant person, or someone who has given secret information about you to the police If I find the rat fink who informed on me, he won't live long enough to do it again.

Common Names:

Name	Pronounced	Usage
Boyd	BOID (English)	Scottish, English
AmbrÓSio	əm-BRAW-zyoo	Portuguese
Anthousa	-	Ancient Greek
Fenella	-	Scottish
Theobald	THEE-ə-bawld (English)	English (Rare), Ancient Germanic
Ulysses	yoo-LIS-eez (English)	Roman Mythology, English