1. a progam that protects a computer from malware and other forms of outside intrusion

2. any protective barrier between two places
My firewall needs to be updated.
by Light Joker August 26, 2007

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The best tool to prevent windows from accessing the activation server and disabling your version. Also it prevents windows from using your bandwidth to download useless "updates".
The firewall totally stonewalls the windows activation processes !
by chemical_processes May 24, 2010

The Urban Dictionary Mug

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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).

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Section of aircraft especially designed to allow all engine heat and smoke to fill the cockpit.
Good thing my cessna 172 has a firewall....oh crap! the engine is on fire!
by IrishRepublicanArmy December 22, 2003

The Urban Dictionary Mug

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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).

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Either a tool used to protect your computer from outside invaders, or a complete jackass who pretends to be a programmer in just about every language other than Visual Basic. Makes himself feel better by creating false definitions of people with a higher capacity of thinking than his own. Tends to think that Windows, despite it being the most popular Operating System in the world, is a horrible platform to dev for (as if it would matter for him).
Uses strange misspellings of words in order to seem cool, but it does the opposite.
"FireWall (Unknown@CAUniversity.Freelance.us) has left #DigitalUnderground (ooo0ooo, a FireWall just blocked your biznitch ass. What cha going to do biznitch?)"
by Faero August 16, 2004

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

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.

Buy the mug

The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

Buy the t-shirt

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