light·​fast ˈlīt-ˌfast How to pronounce lightfast (audio)
: resistant to light and especially to sunlight
especially : colorfast to light
lightfastness noun

Word History

First Known Use

1904, in the meaning defined above

Time Traveler
The first known use of lightfast was in 1904

Dictionary Entries Near lightfast

Cite this Entry

“Lightfast.” Dictionary, Merriam-Webster, Accessed 2 Jun. 2023.

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