photochromic lens

photochromic lens definition - medical

pho·to·chro·mic lens (fōˌtə-krōˈmĭk)

noun
A light-sensitive eyeglass lens that automatically darkens in sunlight and clears in reduced light.

The American Heritage® Medical Dictionary Copyright © 2009 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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