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Idiopathic \Id`i*o*path"ic\, Idiopathical \Id`i*o*path"ic*al\, a. [Cf. F. idiopathique.] (Med.) Pertaining to idiopathy; characterizing a disease arising primarily, and not in consequence of some other disease or injury; -- opposed to {symptomatic}, {sympathetic}, and {traumatic}. -- {Id`i*o*path"ic*al*ly}, adv.
idiopathic adj : (of diseases) arising from an unknown cause; "idiopathic epilepsy"