dysadaptation

noun
dys·​ad·​ap·​ta·​tion | \ dis-ˌad-ˌap-ˈtā-shən, -əp- How to pronounce dysadaptation (audio) \

Medical Definition of dysadaptation

: an impaired ability of the iris and retina to adapt properly to variations in light intensities that is often indicative of vitamin A deficiency