Claudication

Claudication (from the Latin "to limp") describes a symptom where a patient has impairment, pain, discomfort, numbness or tiredness in the legs while walking or standing, but which is relieved when the patient rests. It most commonly affects the calves, but can also affect the feet, thighs, hips, buttocks, or even the arms. 
The level of impairment is measured by how long the patient has to walk before the onset of symptoms. This level is usually described as "blocks", which measures a distance of 100 meters - a typical city block. As such, if the impairment appears after 200 meters of walking, it is described clinically as "Two block claudication". 
Claudication can be caused by many conditions, such as poor circulation, or a compressed nerve, so a further differential diagnosis is required. Circulatory claudication has a poor prognosis, but pharmaceutical treatment can help with the symptoms. Nerve claudication can usually be treated with surgery. 
Claudication of the jaw while chewing is typical of giant cell arteritis.
Claudication at Wikipedia