What is.....

shank
noun
1. Anatomy . the part of the lower limb in humans between the knee and the ankle; leg.
2. a corresponding or analogous part in certain animals.
3. the lower limb in humans, including both the leg and the thigh.
4. a cut of meat from the top part of the front (foreshank)  or back (hind shank)  leg of an animal.
5. a narrow part of various devices, as a tool or bolt, connecting the end by which the object is held or moved with the end that acts upon another object.