A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape.

As a component of furniture, it is used for the economy of materials needed to provide the support for the useful surface, such as the table top or chair seat.

In humans and other mammals, a leg includes the bones, muscles, tendons, ligaments, blood vessels, nerves, and skin.

In tetrapod anatomy, leg is used to refer to the entire limb.

In human medicine, the precise definition refers[2][3][4] only to the segment between the knee and the ankle.