formaldehyde

American  

[fawr-mal-duh-hahyd, fer-] / fɔrˈmæl dəˌhaɪd, fər- /

noun

Chemistry.

• formaldehydes
  plural

1. a colorless, toxic, potentially carcinogenic, water-soluble gas, CH 2 O, having a suffocating odor, usually derived from methyl alcohol by oxidation: used chiefly in aqueous solution, as a disinfectant and preservative, and in the manufacture of various resins and plastics.

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formaldehyde British  

/ fɔːˈmældɪˌhaɪd /

noun

1. Systematic name: methanal.  a colourless poisonous irritating gas with a pungent characteristic odour, made by the oxidation of methanol and used as formalin and in the manufacture of synthetic resins. Formula: HCHO

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formaldehyde Scientific  

/ fôr-măl′də-hīd′ /

1. A colorless gas having a sharp, suffocating odor. It is used in making plastics and, when dissolved in a solution of water and methanol, to preserve biological specimens. Chemical formula: CH ₂ O.

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Other Word Forms

Noun Inflected Forms

• formaldehydes
  plural

Etymology

Origin of formaldehyde

1870–75; form(ic) + aldehyde; modeled on German Formaldehyd

Compare meaning

How does formaldehyde compare to similar and commonly confused words? Explore the most common comparisons:

• paraformaldehyde vs. formaldehyde

Explanation

No, formaldehyde is not a formal hiding place. Formaldehyde is a strong-smelling colorless gas. Depending on what other elements are combined with it, formaldehyde is used for embalming, manufacturing, and all kinds of other things. Formaldehyde is really good at helping things stick together, which is why it's often used in making things like particleboard and some insulation materials found in buildings. It’s also found in some glues and paints. Besides helping things stick, formaldehyde is famous in science labs for preserving biological specimens, like animals and plants, so that they can be studied without decaying.

Example Sentences

See Examples For:

formaldehyde formaldehydes

Alongside greenhouse gases, gas plants emit fine particulate matter, linked to a range of heart and lung problems; nitrogen oxides, which aggravate respiratory disease; and hazardous air pollutants including mercury, formaldehyde and benzene.

From Barron's ● Aug. 11, 2026

That discovery immediately caught their attention because formaldehyde is produced when methane breaks down in the atmosphere.

From Science Daily ● May 10, 2026

Composite wood products can be bound with formaldehyde.

From BBC ● Mar. 16, 2026

Preserved in formaldehyde and paraffin wax, they come from patients treated at the UK's national bowel hospital, St Mark's, in northwest London.

From Barron's ● Feb. 4, 2026

Animals from foreign lands, preserved in formaldehyde or embalmed and stuffed with sawdust.

From "The City Beautiful" by Aden Polydoros

It is made in small batches and is a 10-free polish, meaning its base is made without formaldehydes, added fragrance and other chemicals commonly found in nail polish.

From Los Angeles Times ● Oct. 14, 2022

Another popular brand for sensitive skin is Vanicream because it’s free of fragrances, parabens, formaldehydes, and other irritating ingredients.

From Slate ● Nov. 6, 2018

What she found terrified her: petrochemicals, formaldehydes and flame retardants in everyday household products from floor cleaners to mattresses.

From Forbes ● May 27, 2015

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