lightproof

adjective

light·​proof ˈlīt-ˌprüf How to pronounce lightproof (audio)
Synonyms of lightproofnext
: 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

light pressure

lightproof

light quantum

See More Nearby Entries 

Cite this Entry

“Lightproof.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lightproof. Accessed 3 Dec. 2024.

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Kids Definition

lightproof

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

More from Merriam-Webster on lightproof

Thesaurus: All synonyms and antonyms for lightproof

Nglish: Translation of lightproof for Spanish Speakers

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