thighbone has definitions from the fields of anatomy,zoology
1
[ noun ] (anatomy,zoology) the longest and thickest bone of the human skeleton; extends from the pelvis to the knee

Synonyms

femoris femur

Used in print

(Mr. America, 4:6...)

Why it was ever forgotten for even a moment I cannot say because it works perfectly for everyone , no_matter whether he has short or long thigh-bone lengths !

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