1923, in the meaning defined above
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Time Traveler for lightproof
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Cite this Entry
“Lightproof.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lightproof. Accessed 4 Aug. 2021.
More from Merriam-Webster on lightproof
Thesaurus: All synonyms and antonyms for lightproof
Nglish: Translation of lightproof for Spanish Speakers
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