astigmatism

• POS: Noun
• HYPHEN: a=stig=ma=tism

CIDE DICTIONARY

astigmatism, n. [Gr. 'a priv. + , , a prick of a pointed instrument, a spot, fr. to prick: cf. F. astigmatisme.].

 A defect of the eye or of a lens, in consequence of which the rays derived from one point are not brought to a single focal point, thus causing imperfect images or indistinctness of vision.  [1913 Webster]
" The term is applied especially to the defect causing images of lines having a certain direction to be indistinct, or imperfectly seen, while those of lines transverse to the former are distinct, or clearly seen."  [1913 Webster]

OXFORD DICTIONARY

astigmatism, n. a defect in the eye or in a lens resulting in distorted images, as light rays are prevented from meeting at a common focus.

Derivative

astigmatic adj.

Etymology

A-(1) + Gk stigma -matos point

ROGET THESAURUS

astigmatism

Dimsightedness

N dimsightedness, dim sight, dull sight half sight, short sight, near sight, long sight, double sight, astigmatic sight, failing sight, dimsightedness, purblindness, lippitude, myopia, presbyopia, confusion of vision, astigmatism, color blindness, chromato pseudo blepsis, Daltonism, nyctalopia, strabismus, strabism, squint, blearedness, day blindness, hemeralopia, nystagmus, xanthocyanopia, xanthopsia, cast in the eye, swivel eye, goggle-eyes, obliquity of vision, winking, nictitation, blinkard, albino, dizziness, swimming, scotomy, cataract, ophthalmia, blinker, screen, deceptio visus, refraction, distortion, illusion, false light, anamorphosis, virtual image, spectrum, mirage, looming, phasma, phantasm, phantasma, phantom, vision, specter, apparition, ghost, ignis fatuus, specter of the Brocken, magic mirror, magic lantern, mirror lens, dim-sighted, myopic, presbyopic, astigmatic, moon-eyed, mope-eyed, blear-eyed, goggle-eyed, gooseberry-eyed, one-eyed, blind of one eye, monoculous, half-blind, purblind, cock-eyed, dim-eyed, mole- eyed, dichroic, blind as a bat, winking.