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22.
1. A person who turns another person in for doing something wrong.

2. Those people in their early twenties who work on school campuses and whose only purpose is to inform teachers when students have done something wrong. They are usually seen riding golf-carts, staring off into space, chatting it up on walking-talkies,and generally acting as if they have something important and relevent that they are doing when, in fact, they are completely useless.
1. Man, my sister is such a narc, she told our parents I snuck out of the house last night.

2. The stupid Narc almost ran me off the sidewalk and then had the nerve to yell at me because I was on the grass!
by Hallucination-Walker July 06, 2006
 
23.
Narc is a shortened form of Narcotic and may refer to hard drugs or, by extension to a police officer from the drugs squad.

NB:
This word is often confused with nark. Nark is British and Australian slang for
(i) noun: a police informer, or more widely, anyone who reports illegal or anti-social activities to any authorities.
(ii) verb: to annoy, to irritate,
"See, that guy over there? The one who looks like a druggie? He's undercover, he's a narc."

"That guy just asked me for money for a cup of coffee"
"Cup of coffee? He's a junky, he wants his narcs."
by PaulQ86 February 16, 2012
 
24.
A narcissist.
He is a narc, all about himself, no empathy for others.
by Sam688 December 30, 2010
 
25.
Short abbreviation for "narcissist", which means conceited, self-obsessed, bigheaded.
...also a very good Interpol song
Johnny is such a Narc, all he thinks about is himself.
by Meeneh December 26, 2004
 
26.
To suddenly and uncontrollably fall into deep sleep. Typically in the form of a full night's rest or extended nap. Derivative of the word "narcoleptic."
"Sorry I narced out last night in the middle of the movie; I really wanted to watch it with you."
by Jon Hoffman July 04, 2006
 
27.
1. To 'narc', is to get angry/cut/mad at someone and be nagging/yelling all in their face and shit.
Therefore a narc is anyone who gets angry in this manner.
1. "If I get home too late my old lady will be narcking."
"I hope my woman doesn't narc me for stinking like booze."
"My woman is a narc/narcker."
by Diego August 14, 2003