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

Everything from polyurethane foams with formaldehyde and TCEP (a flame retardant) to phthalates can end up in nonorganic mattresses, off-gassing into your home. —Scott Gilbertson, Wired News, 16 June 2025

Recent research says that biofuel refiners also emit significant amounts of carcinogenic and dangerous substances, including hexane and formaldehyde, in greater amounts than petroleum refineries. —ArsTechnica, 14 June 2025

Some have shea butter, others are packed with formaldehyde releasers and other harmful chemicals, explained Elissia Franklin, an analytical chemist at Silent Spring, in a press statement. —Jenny Lehmann, Discover Magazine, 9 May 2025

The European Union banned formaldehyde as a cosmetic ingredient in 2009, and any cosmetic product containing a formaldehyde-releasing preservative above a miniscule concentration must include a warning. —Ronnie Cohen, NPR, 8 May 2025

Word History

Etymology

International Scientific Vocabulary form- + aldehyde

First Known Use

1872, in the meaning defined above

Phrases Containing formaldehyde

• urea-formaldehyde

Rhymes for formaldehyde

• acetamide
• acetonide
• acidified
• antimonide
• beatified
• benzaldehyde
• borohydride
• chalcogenide
• commodified
• decalcified
• declassified
• disaccharide

Kids 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