1) An annoying person 2) Annoy 3) Betrayer 4) Blabber 5) British informant 6) British informer 7) British stool pigeon 8) British stoolie 9) Cause annoyance in 10) DEA agent 11) Drugbuster 12) English informant 13) Inform or spy 14) Informer 15) Informer or spy 16) Informer to Scotland Yard 17) Informer, slang 1) Annoy 2) Antagonize 3) Beset 4) Chevvy 5) Chevy 6) Chivvy 7) Chivy 8) Harass 9) Harry 10) Irritate 11) Narc 12) Peeve 13) Rankle 14) Rat 15) Rile 16) Vex 
Spoilsport.
Nark is British, Australian and New Zealand slang for an informer or spy, especially one working for the police.
[n] - (British) an informer or spy working for the police 2. [v] - inform or spy (for the police)
British, Australian and New Zealand slang for an informer or spy, especially one working for the police.
copper`s nark noun an informer or spy working for the police
If someone is in a nark, it means they are in a bad mood, or being grumpy. It's also the word for a spy or informant. For example a coppers nark is someone who is a police informant
a stool pigeon or informer. · an annoying person.