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1. Someone acting as an informer or decoy for the police
   - snitch, snitcher, stoolpigeon, stool pigeon, stoolie [N. Amer], sneak, sneaker, canary [N. Amer], grass [Brit]

1. Take the place of work of someone on strike
   - scab, rat, blackleg [Brit]
    
2. Confess to a punishable or reprehensible deed, usually under pressure
   - confess, squeal

Derived forms: finked, finks, finking

Type of: acknowledge, admit, betrayer, blabber, do work, informer, rat, squealer, work

Encyclopedia: Fink