An informer; a tell-tale; one who turns queen's (or king's) evidence.(noun)
A handcuff.(noun)
The Century Dictionary (Public Domain)
Use "snitcher" in a sentence
"Winwood, the poet-forger, the snitcher, the coward, and the stool, was returned for a fresh forgery."
"But if my kid was a gang member, then all this would end with a couple of conversations held with the snitcher or a simple call to the prosecutor..."
"News of this latest attempt to restore Sunday school standards in the White House reached the outside world via a memo snuck out to a Washington Post reporter by a heroic whistle blower and/or leaker-snitcher, depending on your ethical standards."