astigmatism

astigmatism [uh-stig-muh-tiz-uh m] ExamplesWord Origin noun

1. 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.
2. 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 Examples from the Web for astigmatism Historical Examples of astigmatism

If you don’t just see things as they see them, you’re troubled with astigmatism.

The Trail of ’98

Robert W. Service

You must see some good oculist about your astigmatism, my dear.

A Book of Burlesques

H. L. Mencken

To her it was as though her own eyesight were normal, and astigmatism the rule among other people.

Athalie

Robert W. Chambers

To such let me explain that I am suffering from astigmatism.

Humorous Ghost Stories

Dorothy Scarborough

A diagram similar to Fig. 394 is used as a test for astigmatism.

Physics

Willis Eugene Tower

British Dictionary definitions for astigmatism astigmatism astigmia (əˈstɪɡmɪə) noun

1. a defect of a lens resulting in the formation of distorted images; caused by the curvature of the lens being different in different planes
2. faulty vision resulting from defective curvature of the cornea or lens of the eye

Word Origin and History for astigmatism n.

1849, coined by the Rev. William Whewell (1794-1866), English polymath, from Greek a- “without” (see a- (3)) + stigmatos genitive of stigma “a mark, spot, puncture” (see stick (v.)).

astigmatism in Medicine astigmatism [ə-stĭg′mə-tĭz′əm] n.

1. 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

Related formsas′tig•mat′ic (ăs′tĭg-măt′ĭk) adj. n. astigmatism in Science astigmatism [ə-stĭg′mə-tĭz′əm]

1. 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.

astigmatism in Culture 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.