Did you try Googling the phrase before taking the time to post a question here? That would have been much faster. I Googled it for you - here are the results.
Could you please tell me what 'coppers' nark' mean exactly, and if it could be used in everyday English as a common expression?
(I suppose it's got sth to do with 'shopping Sb' and 'telling on Sb perhaps?!)
Thanks dear emsr2d2. Actually I did, but the problem is they would mostly give you the fixed definition while at the moment I came across the expression I asked myself if it was commonly used in contexts other than those related to police stuff (such as the time when a friend tells on a person and consequently be addressed as 'coppers' nark' (?!)
No, we wouldn't use it to refer to anybody other than a police informant. That's why the word "copper's" is in the phrase. "Copper" is a very informal/slang term for a police officer. I wouldn't recommend using it with anyone these days. There are worse words used for police officers but in the UK, the police officers I know (although they don't mind referring to each other as coppers) dislike it when people outside the police force use it.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.
Also, 'copper's nark' is rather dated. In American TV dramas they often use 'CI' (Confidential Informant).
Now I think it's mainly used for police informants. Though in the episode I was watching it was just used to refer to a friend who'd told someone something he shouldn't have.
Thanks a lot for the reply.
"CI" is police-talk. To the one's being informed on the person is a narc. (Note, the root is from "narcotics.")
(Not a Teacher)
In the US, 'narc' also refers to a drug enforcement officer, particularly an undercover one.
But like the others said, it could also be an informant, usually involved with illegal substances.