WordWeb Online

1. [Brit, slang] An informer or spy working for the police
   - copper's nark [Brit, slang]
    
2. [N. Amer, informal] A lawman concerned with narcotics violations
   - narc [N. Amer, informal], narcotics agent, narco [N. Amer, informal]

1. Cause annoyance in; disturb, especially by minor irritations
   "Mosquitoes buzzing in my ear really narks me";
   - annoy, rag, get to, bother, get at [informal], irritate, rile, nettle, gravel [US], vex, chafe, devil, tick off [informal], roil [N. Amer]
    
2. Inform or spy (for the police)

Sounds like: naps, knaps, napnark

Derived forms: narked, narking, narks

Type of: betrayer, blabber [informal], displease, inform, informer, law officer, lawman, peace officer, rat [informal], squealer

Encyclopedia: Nark, Iran