the measured distance that a patient can walk before he or she is stopped by pain in the muscles, usually the calf muscles, or breathlessness. It is a useful estimate of the degree of impairment of the blood supply. See claudication.
(of the eye) the distance between the lens and the point behind the lens at which light from a distant object is focused. In a normally sighted person the point of focus is on the retina, but in *myopia (short-sightedness) the focus is in front of the retina and in *hypermetropia (long-sightedness) the point of focus is beyond the retina.... focal distance
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