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1 definition by F-Laboyrie

 
1.
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