astigmatism

noun astig·ma·tism \ ə-ˈstig-mə-ˌti-zəm \
Updated on: 13 Dec 2017

Definition of astigmatism

1 : a defect of an optical system (such as a lens) causing rays from a point to fail to meet in a focal point resulting in a blurred and imperfect image
2 : a defect of vision due to astigmatism of the refractive system of the eye and especially to corneal irregularity
3 : distorted understanding suggestive of the blurred vision of an astigmatic person

Recent Examples of astigmatism from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'astigmatism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of astigmatism

1831


ASTIGMATISM Defined for English Language Learners

astigmatism

noun

Definition of astigmatism for English Language Learners

  • medical : a problem with the eye that prevents a person from seeing clearly


Medical Dictionary

astigmatism

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

medical Definition of astigmatism

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 : 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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