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lightfast

American

[lahyt-fast, -fahst] / ˈlaɪtˌfæst, -ˌfɑst /

adjective

not affected or faded by light, especially sunlight; colorfast when exposed to light.

Other Word Forms

lightfastness

noun

Etymology

Origin of lightfast

First recorded in 1955–60; light ¹ + fast ¹

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.