From the movie the arrival when the aliens legs go in backwards. It is an action to give someone Alien Legs means to kick their legs in.
Hey your better shut the hell up or i'll give you alien legs.
by Drew June 28, 2004

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Top Definition
A mafia-style torture, where the victims legs are made to bend at the knee the opposite way they usually do, making the victim look like an alien.
Christ, what did they do to his knees? Can he even walk?

Oh, you know, he was hanging with the wrong crowd, someone gave him the old alien legs.
by Evan Wunsch March 29, 2005

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).

Buy the t-shirt