lightproof

adjective

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

Examples of lightproof in a Sentence

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Indeed, the first camera was essentially a lightproof box with a pinhole-size hole in one side. — IEEE Spectrum, 11 Oct. 2023

Word History

First Known Use

circa 1788, in the meaning defined above

Time Traveler
The first known use of lightproof was circa 1788

Rhymes for lightproof

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Browse Nearby Words

light pressure
lightproof
light quantum
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Cite this Entry

“Lightproof.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lightproof. Accessed 28 Oct. 2026.

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Kids Definition

lightproof

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

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