For No Reason Boner. When you randomly get a boner for no reason, mostly in class or a meeting.
"Man I got the biggest FNRB today in class, it was AWESOME!"

or

Since I have a FNRB, will you give me an OTPHJ?
by wowihavethebiggestFNRBrightnow April 13, 2011

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Top Definition
For No Reason Boner

Used often when one wants to discreetly express the fact that he is currently experiencing a boner for no apparent reason at all.
Dude 1: They just called your name... go get that diploma.

Dude 2: Shit. I don't know what to do. I've got a F.N.R.B.!

Dude 1: Ouch. Bad timing
by Worldwide Thugs September 13, 2006

The Urban Dictionary Mug

Lotsa space for your liquids.

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The Urban Dictionary Mug

Lotsa space for your liquids.

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The Urban Dictionary Mug

Your favorite word on a white mug.

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The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

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The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

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The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

Buy the t-shirt