the definition of astigmatism

1.Also calledastigmia [ uh - stig -mee- uh ]/əˈstɪg mi ə/ ( Show IPA ) .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.First recorded in1840-50;astigmat(ic) + -ism Examples from the Web forastigmatism

  • I haveastigmatismin one eye, and have therefore to wear special spectacles.

    The Girls of St. Wode's L. T. Meade
  • A diagram similar to Fig. 394 is used as a test forastigmatism .

    Physics Willis Eugene Tower
  • To such let me explain that I am suffering fromastigmatism .

    Humorous Ghost Stories Dorothy Scarborough
  • There is one other defect of vision that is so common as to call for a word; this isastigmatism .

    Physiology Ernest G. Martin
  • There seems to be a sort ofastigmatismthat keeps us from seeing things straight.

    Quiet Talks on Service S. D. Gordon
  • One of the most common forms of defective vision isastigmatism .

    Initiative Psychic Energy Warren Hilton
  • When this form ofastigmatismis excessive, it may be corrected by the use of spectacles fitted with cylindrical lenses.

    Curiosities of Light and Sight Shelford Bidwell
  • That's no reason for calling in the neighbors

    to rejoice with him because he hasastigmatism .

    The Vision Spendid William MacLeod Raine
  • astigmatismproduced by the incision is corrected with glasses.

    A System of Operative Surgery, Volume IV (of 4) Various
  • In Manitou when men get drunk, the people getastigmatismand can't see the tangledfooted stagger.

    The World For Sale, Complete Gilbert Parker
British Dictionary definitions forastigmatism 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 planes2.faulty vision resulting from defective curvature of the cornea or lens of the eyeWord Origin and History forastigmatismn.

1849, coined by the Rev. William Whewell (1794-1866), English polymath, from Greeka-"without" (see a- (3)) +stigmatosgenitive ofstigma"a mark, spot, puncture" (see stick (v.)).

astigmatismin Medicine

astigmatism a·stig·ma·tism (ə-stĭg'mə-tĭz'əm)
n.
A condition in which unequal curvatures along the different meridians in one or more of the refractive surfaces of the eye cause the rays from a light source not to be focused at a single point on the retina. Also called astigmia .

as'tig·mat'ic (ās'tĭg-māt'ĭk) adj. & n. astigmatismin Science
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.
astigmatismin Cultureastigmatism [(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.


Category: Astigmatism

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