focal epilepsy - epilepsy in which the attack begins with an isolated disturbance of cerebral function (as a twitching of a limb or an illusory sensation or a mental disturbance)epilepsy - a disorder of the central nervous system characterized by loss of consciousness and convulsions focal seizure - transitory disturbance in motor or sensory function resulting from abnormal cortical activity Jacksonian epilepsy - focal epilepsy in which the attack usually moves from distal to proximal limb muscles on the same side of the body |