astigmatism

[ uh-stig-muh-tiz-uhm ]

/ əˈstɪg məˌtɪz əm /

noun

Also called a·stig·mi·a

[uh-stig-mee-uh]. /əˈstɪg mi ə/. Ophthalmology. a refractive error of the eye in which parallel rays of light from an external source do not converge on a single focal point on the retina.

Optics. an aberration of a lens or other optical system in which the image of a point is spread out along the axis of the system.

Origin of astigmatism

First recorded in 1840–50; astigmat(ic) + -ism

Words nearby astigmatism

asthmatic, as though, Asti, astigmatic, astigmatic lens, astigmatism, astigmatizer, astigmatometer, astigmatoscope, astigmatoscopy, astigmia

Dictionary.com UnabridgedBased on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for astigmatism

He was shortsighted, but had no astigmatism; tests of the field of vision showed no abnormality.
Vocational Psychology: Its Problems and Methods|Harry L. Hollingworth
One of the most common forms of defective vision is astigmatism.
Initiative Psychic Energy|Warren Hilton
When a child holds his head to one side constantly on looking at objects, astigmatism, an error of eyesight, is usually indicated.
The Mother and Her Child|William S. Sadler
There seems to be a sort of astigmatism that keeps us from seeing things straight.
Quiet Talks on Service|S. D. Gordon

Another peculiarity by which the eye is affected, and which does not occur in optical instruments, is that known as astigmatism.
Curiosities of Light and Sight|Shelford Bidwell

British Dictionary definitions for astigmatism

astigmatism

astigmia (əˈstɪɡmɪə)

/ (əˈstɪɡməˌtɪzəm) /

noun

a defect of a lens resulting in the formation of distorted images; caused by the curvature of the lens being different in different planes

faulty vision resulting from defective curvature of the cornea or lens of the eye

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for astigmatism

astigmatism

[ (uh-stig-muh-tiz-uhm) ]

A condition in which the curvature of the cornea of the eye is uneven, causing a blurring of vision. Astigmatism is normally corrected by glasses.

Medical definitions for astigmatism

astigmatism

[ ə-stĭg′mə-tĭz′əm ]

n.

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.astigmia

Other words from astigmatism

as′tig•mat′ic (ăs′tĭg-măt′ĭk) adj. n.

Scientific definitions for astigmatism

astigmatism

[ ə-stĭg′mə-tĭz′əm ]

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 a single point on the retina, resulting in blurred vision.

单词	astigmatism
释义	astigmatism [ uh-stig-muh-tiz-uhm ] / əˈstɪg məˌtɪz əm / noun Also called a·stig·mi·a [uh-stig-mee-uh]. /əˈstɪg mi ə/. Ophthalmology. a refractive error of the eye in which parallel rays of light from an external source do not converge on a single focal point on the retina. Optics. an aberration of a lens or other optical system in which the image of a point is spread out along the axis of the system. Origin of astigmatism First recorded in 1840–50; astigmat(ic) + -ism Words nearby astigmatism asthmatic, as though, Asti, astigmatic, astigmatic lens, astigmatism, astigmatizer, astigmatometer, astigmatoscope, astigmatoscopy, astigmia Dictionary.com UnabridgedBased on the Random House Unabridged Dictionary, © Random House, Inc. 2020 Example sentences from the Web for astigmatism He was shortsighted, but had no astigmatism; tests of the field of vision showed no abnormality. Vocational Psychology: Its Problems and Methods\|Harry L. Hollingworth One of the most common forms of defective vision is astigmatism. Initiative Psychic Energy\|Warren Hilton When a child holds his head to one side constantly on looking at objects, astigmatism, an error of eyesight, is usually indicated. The Mother and Her Child\|William S. Sadler There seems to be a sort of astigmatism that keeps us from seeing things straight. Quiet Talks on Service\|S. D. Gordon Another peculiarity by which the eye is affected, and which does not occur in optical instruments, is that known as astigmatism. Curiosities of Light and Sight\|Shelford Bidwell British Dictionary definitions for astigmatism astigmatism astigmia (əˈstɪɡmɪə) / (əˈstɪɡməˌtɪzəm) / noun a defect of a lens resulting in the formation of distorted images; caused by the curvature of the lens being different in different planes faulty vision resulting from defective curvature of the cornea or lens of the eye Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Cultural definitions for astigmatism astigmatism [ (uh-stig-muh-tiz-uhm) ] A condition in which the curvature of the cornea of the eye is uneven, causing a blurring of vision. Astigmatism is normally corrected by glasses. The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved. Medical definitions for astigmatism astigmatism [ ə-stĭg′mə-tĭz′əm ] n. 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.astigmia Other words from astigmatism as′tig•mat′ic (ăs′tĭg-măt′ĭk) adj. n. The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. Scientific definitions for astigmatism astigmatism [ ə-stĭg′mə-tĭz′əm ] 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 a single point on the retina, resulting in blurred vision. The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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