1 definition by F-Laboyrie

Top Definition
Basically, you have normal thighs, then they get fat (tier 1). But when they get like even fatter, you get another level of fat like a hill of fat(tier 2), which is loose off the other fat so when a thunder thigh is being walked besides the legs (tier 1) rubbing against eachother they (tier 2) hit eachother making a noise, hence thunder coming into the expression, most likely to because of alliteration for a dramatic, comedic affect. This sound can have a brighter tone and richer feel if accentuated with bumpy cellulite
Damn, those thunder thigs are so massive it looks like shes got a second arse

It's like someones stuck balloons in those thunder tighs

No, no....come on, this cant be real, that girls got thunder thighs ripping out like the hulk
by F-Laboyrie May 31, 2007

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