lightfast

American  

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

adjective

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

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Other Word Forms

• lightfastness noun

Etymology

Origin of lightfast

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

Example Sentences

The cathedral received one of 12 copies of the “Apostle’s Edition” of the Bible, produced on 100% cotton paper using what its creators say is “lightfast ultraviolet ink” that dries “instantly on the press” before another color is applied.

From Washington Times

Ironically, the red paint made decades ago was relatively lightfast, because the color came from iron oxide, which keeps its color in the sun just as red, iron-rich soil found in some parts of the country does.

From Washington Post

Wax-based pigments tend to be lightfast, but watercolors and markers fade, so their tints will need to be corrected as well.

From Scientific American