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Medical Dictionary

astigmatism

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noun astig·ma·tism \ə-ˈstig-mə-ˌtiz-əm\

Medical Definition of astigmatism

  1. 1:  a defect of an optical system (as a lens) causing rays from a point to fail to meet in a focal point resulting in a blurred and imperfect image

  2. 2:  a defect of vision due to astigmatism of the refractive system of the eye and especially to corneal irregularity—compare emmetropia, myopia





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