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
Household chemicals—Many cleaning products contain harmful substances like formaldehyde and benzene, both volatile organic compounds (VOCs).
—
Brynn Cooksey, Forbes.com, 1 June 2025
About 4% of the products used contained formaldehyde or formaldehyde-releasing preservatives, but more than half of the women—53%—reported using them.
—Kaitlin Sullivan, Health, 17 May 2025
That includes formaldehyde and extremely high levels of ammonia, which react with each other to form amino acids under the right conditions.
—Michael Irving, New Atlas, 30 Jan. 2025
Wear gloves while cleaning or handling chemicals (such as formaldehyde) that could cause reactions or staining in the nails.
Perform regular maintenance on manicures.
—Jenny Berg, Allure, 27 Jan. 2025
See All Example Sentences for formaldehyde
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Brynn Cooksey, Forbes.com, 1 June 2025
About 4% of the products used contained formaldehyde or formaldehyde-releasing preservatives, but more than half of the women—53%—reported using them.
—Kaitlin Sullivan, Health, 17 May 2025
That includes formaldehyde and extremely high levels of ammonia, which react with each other to form amino acids under the right conditions.
—Michael Irving, New Atlas, 30 Jan. 2025
Wear gloves while cleaning or handling chemicals (such as formaldehyde) that could cause reactions or staining in the nails.
Perform regular maintenance on manicures.
—Jenny Berg, Allure, 27 Jan. 2025
See All Example Sentences for formaldehyde
Cite this Entry
“Formaldehyde.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/formaldehyde. Accessed 10 Jun. 2025.
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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