hydrogen peroxide

noun

: an unstable compound H2O2 used especially as an oxidizing and bleaching agent, an antiseptic, and a propellant

Examples of hydrogen peroxide in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Make a paste of two parts baking soda with one part hydrogen peroxide. Melissa Locker, Southern Living, 15 Mar. 2026 To save them, remove the mold by washing them thoroughly with water to remove surface fungi, then spray them with a diluted solution of hydrogen peroxide (1 part hydrogen peroxide to 2 parts water). Sj McShane, Martha Stewart, 13 Mar. 2026 Whitening strips blend both the natural process of oil pulling with hydrogen peroxide to safely and effectively release oxygen and hydroxyl free radicals for a brighter, whiter smile in as soon as 14 days. Tory Johnson, ABC News, 12 Mar. 2026 The team discovered that in October 2018, hospital staff began draining the water tanks every day and stopped the daily monitoring of hydrogen peroxide concentration and disinfection of the water circuits every 14 days as recommended by the manufacturer. Judy L. Thomas, Kansas City Star, 10 Mar. 2026 See All Example Sentences for hydrogen peroxide

Word History

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of hydrogen peroxide was in 1872

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Cite this Entry

“Hydrogen peroxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen%20peroxide. Accessed 21 Mar. 2026.

Kids Definition

hydrogen peroxide

noun
: an unstable liquid compound containing hydrogen and oxygen and used especially for bleaching and as an antiseptic

Medical Definition

hydrogen peroxide

noun
: an unstable compound H2O2 used especially as an oxidizing and bleaching agent and as an antiseptic

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