Definition of "night blindness" []

• 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. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.