ratfink

/ˈrætˌfɪŋk/
noun
  1. A person who is disliked because they inform on others or betray a secret.
    • My little brother is such a ratfink — he ran straight to Mom when I snuck a cookie.
    • Nobody trusted Kevin after he turned out to be a ratfink and told the teacher about the prank.
    • In the old gangster movies, the hero always had to deal with a ratfink who snitched to the police.
Antonyms
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