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
When someone drinks methanol, it’s converted into formaldehyde in the body.
—
Cara Lynn Shultz, People.com, 21 Aug. 2025
That's especially worrisome for Black and Latina women, whom research shows are more often exposed to dangerous ingredients like formaldehyde in nail and hair products.
—Rachel Treisman, NPR, 21 July 2025
The formulas used for extensions often contain formaldehyde, which is also not the safest chemical to have around your eyes.
—Essence, 31 July 2025
Those can include formaldehyde, mercury, asbestos, lead and parabens, which have been linked to cancer, brain damage and reproductive harm.
—Rachel Treisman, NPR, 21 July 2025
See All Example Sentences for formaldehyde
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Cara Lynn Shultz, People.com, 21 Aug. 2025
That's especially worrisome for Black and Latina women, whom research shows are more often exposed to dangerous ingredients like formaldehyde in nail and hair products.
—Rachel Treisman, NPR, 21 July 2025
The formulas used for extensions often contain formaldehyde, which is also not the safest chemical to have around your eyes.
—Essence, 31 July 2025
Those can include formaldehyde, mercury, asbestos, lead and parabens, which have been linked to cancer, brain damage and reproductive harm.
—Rachel Treisman, NPR, 21 July 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 1 Sep. 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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