To grab someone around the neck with your arm, pull their head against your body (thus subduing them), make your other hand into a fist, and grate your knuckles painfully against their scalp. If you're sneaky enough, grabbing them around the neck may not be necessary.

A favorite tactic among bullies and older siblings.
Hey! Don't give me a noogy! It breaks my hair! - My sister
by noogyman February 10, 2005
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The idea that a noogy is rubbing someone on the head is incorrect that is a dutch rub. Anyone who has ever watched Classic Saturday night live knows that a noogy is given by making a fist and extending the knuckle of the middle finger so it sticks out a bit then rapping someone on top of the head with it. This from the classic bits where Bill Murray and Gilda Radner played nerdy schoolkids.
Dude1: What's the matter?
Dude2: that ass Bobby just got a running jump and gave me a flying atomic noogy. I think I might have a concussion.
by Kermit the Bear September 6, 2005
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when someone scratches another being on the head and usually messes up their hair.
Paul gave Caroline a noogy she was very mad, but laughed in spite of herself.
by Caroline Goldsmithers December 18, 2004
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Another term used for a rim-job.
Ew... why would someone want to give a noogy? That would taste like poop.
by ArchieHughes May 31, 2005
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A painful sensation caused by the rubbing of knuckle, fist, or hand to ones head. Generally causing hair displacement and mild cursing.
"Oh man, National Noogie Week is coming up! I'd better run so Sarah doesn't catch me in the middle of her mad noogie spree. Otherwise mass destruction of my hair follicles and/or scalp will occur!"
by Rocked_Socks January 15, 2004
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the act of rubbing one's knuckles on a person's head so as to produce a mildly painful sensation
by Anonymous September 23, 2002
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a painful rubbing of the scalp with the knuckles
He tried to give my friend a noogie and got in trouble for it.
by Light Joker December 19, 2004
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