lightfast

[ lahyt-fast, -fahst ]

adjective

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

Other Words From

• lightfastness noun

Word History and Origins

Origin of lightfast¹

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

Example Sentences

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