- Heberden’s nodes) in and about the last joint of the finger. Sources of vitamin A include animal livers, milk, and yellow and green leafy vegetables which contain carotenes, chemically related substances that are converted to vitamin A in the body. Night blindness is also called day sight, nocturnal amblyopia, nyctalopia and nyctanopia.
* * *night-blind 'nīt-.blīnd adj
* * *the inability to see in dim light or at night. It is due to a disorder of the cells in the retina that are responsible for vision in dim light (see rod), and can result from dietary deficiency of vitamin A. If the vitamin deficiency is allowed to continue, its manifestations may progress to include xerophthalmia and keratomalacia. Night blindness may be caused by other retinal diseases, e.g. retinitis pigmentosa. Congenital stationary night blindness is characterized by poor night vision from early childhood that does not get worse. Medical name: nyctalopia. Compare day blindness.
* * *nyctalopia.
Medical dictionary. 2011.
Look at other dictionaries:
Night blindness — Night Night (n[imac]t), n. [OE. night, niht, AS. neaht, niht; akin to D. nacht, OS. & OHG. naht, G. nacht, Icel. n[=o]tt, Sw. natt, Dan. nat, Goth. nahts, Lith. naktis, Russ. noche, W. nos, Ir. nochd, L. nox, noctis, Gr. ny x, nykto s, Skr. nakta … The Collaborative International Dictionary of English
night-blindness — nightˈ blindness noun Inability to see in a dim light, nyctalopia • • • Main Entry: ↑night … Useful english dictionary
night blindness — n. imperfect vision in the dark or in dim light: a symptom of vitamin A deficiency … English World dictionary
night blindness — nightblind, adj. Ophthalm. a condition of the eyes in which vision is normal in daylight but abnormally poor at night or in a dim light; nyctalopia. [1745 55] * * * ▪ physiology also called nyctalopia failure of the eye to adapt promptly … Universalium
night blindness — the inability to see in dim light or at night. It is due to a disorder of the cells in the retina that are responsible for vision in dim light (see rod), and can result from dietary deficiency of vitamin A. If the vitamin deficiency is allowed to … The new mediacal dictionary
night blindness — night′ blind ness n. oph a condition in which vision is normal in daylight but abnormally poor in dim light • Etymology: 1745–55 night′blind , adj … From formal English to slang
night blindness — noun The optic condition nyctalopia, the inability to see clearly in faint light, as at night Syn: moon blindness … Wiktionary
night blindness — Synonyms and related words: Lombardy leprosy, anemia, ariboflavinosis, beriberi, cachexia, chlorosis, day blindness, deficiency anemia, dermatitis, goiter, greensickness, hemeralopia, keratomalacia, kwashiorkor, maidism, malnutrition, moon… … Moby Thesaurus
night blindness — noun inability to see clearly in dim light; due to a deficiency of vitamin A or to a retinal disorder • Syn: ↑nyctalopia, ↑moon blindness • Hypernyms: ↑visual impairment, ↑visual defect, ↑vision defect, ↑visual disorder, ↑ … Useful english dictionary
night blindness — noun Date: 1754 reduced visual capacity in faint light (as at night) • night blind adjective … New Collegiate Dictionary