noun
mass nounMedicineA condition characterized by an abnormal inability to see in dim light or at night, typically caused by vitamin A deficiency.
‘Fundus examination is usually normal, distinguishing it from the progressive conditions causing nyctalopia.’- ‘The insensitivity to dim stimuli is accompanied by a mild nyctalopia.’
- ‘Ophthalmologists are occasionally confronted with an individual presenting with nyctalopia (ie, a relatively greater difficulty seeing at night).’
- ‘The fact that an abnormal result occurs in 26%, however, suggests that ncytalopia should be evaluated with electrophysiological testing even when the fundi appear normal.’
- ‘About 90% of the female portion of the study suffer from Nyctalopia.’
Origin
Late 17th century via late Latin from Greek nuktalōps, from nux, nukt- ‘night’ + alaos ‘blind’ + ōps ‘eye’.
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