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ametropia

[am-i-troh-pee-uh]
noun Ophthalmology.
  1. faulty refraction of light rays by the eye, as in astigmatism or myopia.

Origin of ametropia

1875–80; < Greek ámetr(os) unmeasured (a- a-6 + métr(on) measure + -os adj. suffix) + -opia
Related formsam·e·trop·ic [am-i-trop-ik, -troh-pik] /ˌæm ɪˈtrɒp ɪk, -ˈtroʊ pɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ametropia

ametropia

noun
  1. loss of ability to focus images on the retina, caused by an imperfection in the refractive function of the eye

Word Origin for ametropia

C19: New Latin, from Greek ametros unmeasured (from a- 1 + metron measure) + ōps 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
ametropia in Medicine

ametropia

[ăm′ĭ-trō′pē-ə]
n.
  1. An eye abnormality, such as nearsightedness, farsightedness, or astigmatism, resulting from faulty refractive ability of the eye.
Related formsam′e•trop′ic (-trŏp′ĭk, -trō′pĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.