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!