femur

(fēˈmər)

1. a. A bone of the leg situated between the pelvis and knee in humans. It is the largest and strongest bone in the body.
   b. A functionally similar bone in the leg or hind limb of a vertebrate animal. Also called thighbone.
2. The thick, most muscular segment of the insect leg, situated between the trochanter and the tibia.

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femur