The thighs of a curvy voluptuous woman, famous in the 70s and early 80s period which adds a seductive, sensual appeal to the whole persona of the woman; unlike a skinny, lean pair of legs so much in fashion and so desired now.
n. A person who is so overweight that one's thighs rub together when he/she walks and creates a low rumbling noise deep within the earth whenever he/she steps.
This word is used to describe a really fat person. A thunderthighs person have really big thighs, make loud farts, constipate, and eat a lot. A thunderthighs person also annoys people a lot. A thuderthighs person also brags and has no sportsmanship. This is my message to you: Don't be a thunde-rthighs person because a thunderthighs human is an annoying bastard.