Definitions:

1. a law enforcement officer concerned with narcotics violations noun
   • Narks are a special kind of police.
2. an informer or spy working for the police noun
   • Let's beat feet. That dude looks like a nark.
3. cause annoyance in verb
   • It really narks them when the neighbors blast their music until early in the morning.
4. inform or spy (for the police) verb
   • The gangster code requires that one never nark.

Synonyms:

• copper's nark
• narc
• rag