from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An eye abnormality, such as nearsightedness, farsightedness, or astigmatism, resulting from faulty refractive ability of the eye.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of several disorders of the eye (spherical or cylindrical) resulting from faulty refractive ability.
from the GNU version of the Collaborative International Dictionary of English
- n. a visual impairment resulting from faulty refraction of light rays in the eye. Subtypes include myopia astigmatism and hyperopia.
from The Century Dictionary and Cyclopedia
- n. A condition of the eye which is abnormal with respect to refraction: the opposite of emmetropia. It comprises myopia, hypermetropia, presbyopia, and astigmatism. See these words.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. (ophthalmology) faulty refraction of light rays in the eye as in astigmatism or myopia
Greek ametros, without measure (a-, without; see a-1 + metron, measure; see meter1) + -opia.(American Heritage® Dictionary of the English Language, Fourth Edition)