snitch
n. countablen. someone who tells a person in authority, like a teacher or the police, that someone else did something wrong. People usually use this word to show they do not like or trust that person.
n. an informant who provides information about others' illicit or prohibited activities to an authority figure. Often carries a strong pejorative connotation within peer groups or criminal subcultures.
Nobody likes a snitch who tells on their friends.
The gang suspected there was a snitch in their group after the police arrived exactly when the deal was happening.
In many tight-knit communities, being labeled a snitch is a social death sentence that results in total isolation and the loss of protection from the group.
Origin uncertain. Perhaps an alteration of Middle English snacche (“a trap, snare”), snacchen (“to seize (prey)”, whence modern English snatch). Compare also Middle English snik snak (“a sudden blow, snap”). Alternatively, perhaps from a dialectal variant of sneak, from Middle English sniken, from Old English snīcan (“to creep; crawl”). More at sneak.
Commonly used as a derogatory label for someone who breaks a code of silence.