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.
Before using hydrogen peroxide on your bathroom floors, consider what type of material they’re made of. — Karen Brewer Grossman, Southern Living, 4 Sep. 2026 But according to Williams, light causes hydrogen peroxide to break down faster, which is why it’s sold in brown bottles. — Michelle Mastro, The Spruce, 31 Aug. 2026 The hydrogen peroxide treatment then attacks the remaining dye-cotton linkages and removes residual color. — Alexandra Harrell, Footwear News, 26 Aug. 2026 McGowen recommends mixing it with hydrogen peroxide to form a paste, then leaving it on for 20 to 30 minutes. — Lauren Dana Ellman, Travel + Leisure, 19 Aug. 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

Rhymes for hydrogen peroxide

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Browse Nearby Words

hydrogen oxide
hydrogen peroxide
hydrogen selenide
See all Nearby Words

Cite this Entry

“Hydrogen peroxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen%20peroxide. Accessed 4 Sep. 2026.

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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

More from Merriam-Webster on hydrogen peroxide

Britannica.com: Encyclopedia article about hydrogen peroxide

Last Updated: - Updated example sentences
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