photochromic

[foh-tuh-kroh-mik]

adjective

(of chemically treated glass or plastic) capable of darkening or changing color when exposed to light.

Origin of photochromic

First recorded in 1950–55; photo- + chrom- + -ic

Related formspho·to·chro·mism, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for photochromic

photochromic

adjective

(of glass) changing colour with the intensity of incident light, used, for example, in sunglasses that darken as the sunlight becomes brighter

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012