formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd 
fər-
: a colorless pungent irritating gas CH2O used chiefly in aqueous solution as a disinfectant and preservative and in chemical synthesis
Examples of formaldehyde in a Sentence
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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
Another five products failed for PFAS, six for alkylphenols and alkylphenol ethoxylates, three for bisphenol A, two for formaldehyde, and three for heavy metals.
—Jasmin Malik Chua, Sourcing Journal, 4 Feb. 2026
Meanwhile, regulators have previously fined the plant for violations involving volatile organic compounds, methanol, and formaldehyde.
—Ken Silverstein, Forbes.com, 28 Jan. 2026
Her brain should be kept in formaldehyde and studied by scientists in the future as a specimen of Realitus televisus.
—Rafaela Bassili, Vulture, 27 Jan. 2026
See All Example Sentences for formaldehyde
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Neetika Walter, Interesting Engineering, 9 Feb. 2026
Another five products failed for PFAS, six for alkylphenols and alkylphenol ethoxylates, three for bisphenol A, two for formaldehyde, and three for heavy metals.
—Jasmin Malik Chua, Sourcing Journal, 4 Feb. 2026
Meanwhile, regulators have previously fined the plant for violations involving volatile organic compounds, methanol, and formaldehyde.
—Ken Silverstein, Forbes.com, 28 Jan. 2026
Her brain should be kept in formaldehyde and studied by scientists in the future as a specimen of Realitus televisus.
—Rafaela Bassili, Vulture, 27 Jan. 2026
See All Example Sentences for formaldehyde
Cite this Entry
“Formaldehyde.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/formaldehyde. Accessed 14 Feb. 2026.
Copy CitationKids Definition
formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd
fər-
: a colorless gas that consists of carbon, hydrogen, and oxygen, has a sharp irritating odor, and when dissolved in water is used to disinfect or to prevent decay
Medical Definition
formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd, fər-
: a colorless pungent irritating gas CH2O used chiefly as a disinfectant and preservative and in chemical synthesis
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