When you aren't feeling it "down there", but your brain(and nervous system) is jstu so overloaded with feeling(usally about a person).
girl one: omg..look at the hot guy!
girl 2: yah..thats michael!
girl 3: wow...omgomgogm! brain ORGASIM!
by THE evil bagel May 29, 2005

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Top Definition
When you're illiterate and you don't know how to spell Brain Orgasm
Timmy tried to define 'brain orgasim'... he didn't know he spelled it incorrectly. Ironic because it has the word Brain in it, inferring thought and logic.
by ClickerMonkey July 21, 2010

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.

Create a mug

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