fink

/fɪŋk/
noun
  1. A person who informs on others to the authorities, especially in a workplace or criminal context; an informer.
    • The workers suspected that someone was a fink, telling the boss about their plans.
    • Nobody trusted him after he acted as a fink during the strike.
    • In the old movies, the gangster called the police informant a dirty fink.
  2. A contemptible or unreliable person.
    • He promised to help but never showed up — what a fink.
    • Don't be a fink and leave your friends to clean up the mess alone.
    • She called him a fink for spreading rumors behind her back.
verb
  1. To inform on someone to the authorities.
    • He finked on his partner to get a lighter sentence.
    • In the old neighborhood, nobody would fink to the police.
    • The student finked to the teacher about who cheated on the test.
  2. To fail to keep a promise or commitment; to back out.
    • He said he'd help us move, but he finked when the day came.
    • She finked out of the agreement at the last minute.
    • Don't fink on your promise to take the kids to the park.