astigmatism

astigmatism definition - medical

a·stig·ma·tism (ə-stĭgˈmə-tĭzˌəm)

noun
A visual defect in which the unequal curvature of one or more refractive surfaces of the eye, usually the cornea, prevents light rays from focusing clearly at one point on the retina, resulting in blurred vision. Also called astigmia.

Related Forms:

  • asˌtig·matˈic (ăsˌtĭg-mătˈĭk) adjective & n.

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astigmatism

Top: astigmatic vision

Bottom: corrected vision

The American Heritage® Medical Dictionary Copyright © 2009 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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