formalin

noun

for·ma·lin ˈfȯr-mə-lən

-ˌlēn

: a clear aqueous solution of formaldehyde and methanol used especially as a preservative

Examples of formalin in a Sentence

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

For example, methylene glycol and formalin are just liquid forms of formaldehyde. — Mira Miller, Verywell Health, 27 Oct. 2023 Some soaps, shampoos, lotions and cleaning products contain formalin, which is formaldehyde dissolved in water. — Claretta Bellamy, NBC News, 17 Oct. 2023 The other half, set in formalin, was eventually sent to the Dayton hospital, the Fellenz's said. — Sarah Volpenhein, jsonline.com, 23 June 2025 Until now, this kind of wet specimen preserved in formalin had been considered unsuitable for RNA analysis. — New Atlas, 3 Aug. 2025 No genetic testing could be done on either specimen due to the deteriorating effects of the formalin used for preservation, which breaks down DNA over time. — Melissa Cristina Márquez, Forbes.com, 19 Apr. 2025 The submersible collected the octopus, preserved its body in alcohol and formalin and sent it to the Field Museum of Natural History in Chicago for study. — Janet Loehrke, USA Today, 26 May 2026 Mammals and reptiles were commonly treated with formalin before being stored in alcohol, while invertebrates were often preserved directly in formaldehyde or mixed solutions containing additives such as glycerol or propylene glycol. — Neetika Walter, Interesting Engineering, 9 Feb. 2026

Word History

Etymology

Formalin, a trademark

First Known Use

1893, in the meaning defined above

Time Traveler

The first known use of formalin was in 1893

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Style

“Formalin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/formalin. Accessed 7 Jul. 2026.

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Medical Definition

formalin

noun

for·ma·lin ˈfȯr-mə-lən, -ˌlēn

: a clear aqueous solution of formaldehyde containing a small amount of methanol

formalin

noun

Examples of formalin in a Sentence

Word History

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