Nyctalopia (n&ibreve_;kt&adot_;lōp&ibreve_;&adot_;), n. [L. nyctalopia, fr. nyctalops a nyctalops, Gr. nyktalwps. Gr. nyktalwps meant, a person affected either with day blindness or with night blindness, and in the former case was derived fr. nyx, nyktos, night + 'wps, 'wpos, the eye; in the latter, fr. nyx + 'alaos blind + 'wps.] (Med.) (a) A disease of the eye, in consequence of which the patient can see well in a faint light or at twilight, but is unable to see during the day or in a strong light; day blindness. (b) See Moonblink.
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&hand_; Some writers (as Quain) use the word in the opposite sense, night blindness. See Hemeralopia.
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