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
Recent Examples on the Web
The carbon isotopes are found on 3I/ATLAS in compounds such as carbon monoxide and carbon dioxide, and even organic molecules such as methanol, formaldehyde and methane.
—
Keith Cooper, Space.com, 30 Mar. 2026
Vanicream has built its reputation on formulas that strip out many of the ingredients most likely to cause reactions—things like fragrance, dyes, lanolin, parabens, and formaldehyde releasers.
—Hana Hong, Glamour, 25 Mar. 2026
Tanning beds—like tobacco, formaldehyde, and asbestos—are classified as a group 1 carcinogen by the World Health Organization's International Agency for Research on Cancer (IARC).
—Tori Crowther, Allure, 19 Mar. 2026
Among the substances mixed with cannabinoids were the anticonvulsant carbamazepine, formaldehyde and fentanyl, among others.
—ABC News, 11 Mar. 2026
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Keith Cooper, Space.com, 30 Mar. 2026
Vanicream has built its reputation on formulas that strip out many of the ingredients most likely to cause reactions—things like fragrance, dyes, lanolin, parabens, and formaldehyde releasers.
—Hana Hong, Glamour, 25 Mar. 2026
Tanning beds—like tobacco, formaldehyde, and asbestos—are classified as a group 1 carcinogen by the World Health Organization's International Agency for Research on Cancer (IARC).
—Tori Crowther, Allure, 19 Mar. 2026
Among the substances mixed with cannabinoids were the anticonvulsant carbamazepine, formaldehyde and fentanyl, among others.
—ABC News, 11 Mar. 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 5 Apr. 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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