light·​proof ˈlīt-ˌprüf How to pronounce lightproof (audio)
: impenetrable by light

Word History

First Known Use

circa 1788, in the meaning defined above

Time Traveler
The first known use of lightproof was circa 1788

Dictionary Entries Near lightproof

Cite this Entry

“Lightproof.” Dictionary, Merriam-Webster, Accessed 19 May. 2024.

Kids Definition


light·​proof ˈlīt-ˈprüf How to pronounce lightproof (audio)
: not letting in light

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