| a condition of the eyes in which vision is normal in daylight but abnormally poor at night or in a dim light; nyctalopia. |
| night blindness n. A condition of the eyes in which vision is normal in daylight or other strong light but is abnormally weak or completely lost at night or in dim light. The condition may result from vitamin A deficiency, disease, or hereditary factors. Also called nyctalopia. |
night blindness n.
See nyctalopia.
night blindness
failure of the eye to adapt promptly from light to darkness that is characterized by a reduced ability to see in dim light or at night. It occurs as a symptom of numerous congenital and inherited retinal diseases or as a result of vitamin A deficiency.
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