dark adaptation

noun Ophthalmology.

the reflex adaptation of the eye to dim light, consisting of a dilatation of the pupil and an increase in the number of functioning rods accompanied by a decrease in the number of functioning cones (opposed to light adaptation).

Origin of dark adaptation

First recorded in 1905–10

Related forms

dark-a·dapt·ed, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Medicine definitions for dark adaptation

dark adaptation

[ därk ]


The adjustment of the eye under reduced illumination, in which sensitivity to light is greatly increased.scotopic adaptation
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.