Top Definition
The act of uncontrollably laughing, or having a giggle fit, at something that could actually be funny, or possibly not. A haver of a sillygasm will convulse while laughing, grab on to things tightly, and can not be easily stopped, as if they were having an orgasmic experience.
Guy: The joke wasn't that funny, but she just started having a sillygasm, I think she was drunk...
by moviesdude3 April 10, 2007

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When one is overwhelmed by the amount of Silly-Bandz one has or the amount a store has in stock!
Mallory got a SILLYGASM because Michael showed her all his 392 Silly-Bandz.
by Mikex4 July 19, 2010

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