Femur is defined as the thighbone, the longest and thickest bone in the body.(noun)
A bone in your body that goes from your pelvis to your knee and that helps you to walk by allowing you to move your leg from the hip to the knee is an example of a femur.
See femur in Webster's New World College Dictionary
See femur in American Heritage Dictionary 4
noun pl. fe·murs or fem·o·ra (fĕmˈər-ə)
Origin: Latin, thigh.
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