per·​ox·​ide | \ pə-ˈräk-ˌsīd How to pronounce peroxide (audio) \

Definition of peroxide

 (Entry 1 of 3)

: a compound (such as hydrogen peroxide) in which oxygen is visualized as joined to oxygen


peroxided; peroxiding

Definition of peroxide (Entry 2 of 3)

transitive verb

: to treat with a peroxide especially : to bleach (hair) with hydrogen peroxide



Definition of peroxide (Entry 3 of 3)

: having or being bleached hair a peroxide blonde

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Other Words from peroxide


peroxidic \ pə-​ˌräk-​ˈsi-​dik How to pronounce peroxidic (audio) \ adjective

Examples of peroxide in a Sentence

Recent Examples on the Web: Noun For those sensitive to peroxide, one option is to decrease the time that the dye remains on your hair, but to color it more frequently. Laura Daily, Washington Post, "You can save money by coloring your hair at home. But should you?," 27 Jan. 2020 Nikita Sursin Ah, the early 2000s—the era of boy bands, Myspace, mirror selfies, and hair that was colored in your basement sink with a bottle of bleach and peroxide, à la Christina Aguilera and Beyoncé. Chloe Metzger, Marie Claire, "How to Go Platinum Blonde Without Destroying Your Hair," 24 Aug. 2018 The vacant gas station had been packed with 45 tons of calcium peroxide when the fire started, and crews were initially unaware that the material, which is used for soil remediation, was being stored there, Sorensen said at the time. Jennifer Johnson,, "Park Ridge Fire Department looks to replace damaged, aging ladder truck," 4 Nov. 2019 But with Overtone, that never happened, probably because the dye is formulated without peroxide and ammonia that's found in many box dyes. Emma Seymour, Good Housekeeping, "Does Overtone Hair Dye Actually Work on Brown Hair?," 10 Dec. 2019 Stewart arrived at a New York photocall for Charlie's Angels yesterday wearing a backwards hat accented by the sprays of piece-y peroxide liberated at strategic angles, the irreverent maneuver furthered by glimpses of her brunette roots. Calin Van Paris, Vogue, "Kristen Stewart Offers a Lesson in the Art of Ball Cap Glamour," 8 Nov. 2019 While fighting the blaze, the fire department learned the building had been packed with 45 tons of calcium peroxide, a hazardous material used for soil remediation, the department said. Jennifer Johnson,, "Park Ridge to owners of fire-damaged former gas station: Tear it down or we will," 16 Oct. 2019 Sorensen said some of the department’s gear and equipment were damaged as a result of the fire because crews were initially unaware that a large amount of calcium peroxide was being stored onsite. Jennifer Johnson,, "Fire-damaged Park Ridge gas station must be demolished, city official says," 20 Aug. 2019 Those attending are reminded to bring canned goods, paper products, household goods or peroxide that will be donated to St. Ignatius. Carol Kovach,, "Lakewood Community, European festivals set for Sept. 7: A Place in the Sun," 3 Sep. 2019 Recent Examples on the Web: Verb Freshly peroxided, Mock headed to the skatepark later that day. Lauren Valenti, Vogue, "How This Skateboarder’s Radical Pink Buzz Cut Caught Frank Ocean’s Attention," 4 Feb. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'peroxide.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of peroxide


1804, in the meaning defined above


1899, in the meaning defined above


1899, in the meaning defined above

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Time Traveler for peroxide

Time Traveler

The first known use of peroxide was in 1804

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Statistics for peroxide

Last Updated

15 Feb 2020

Cite this Entry

“Peroxide.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2020.

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More Definitions for peroxide


How to pronounce peroxide (audio)

English Language Learners Definition of peroxide

: a chemical that is used chiefly to kill bacteria or to make hair lighter in color


per·​ox·​ide | \ pə-ˈräk-ˌsīd How to pronounce peroxide (audio) \

Kids Definition of peroxide


per·​ox·​ide | \ pə-ˈräk-ˌsīd How to pronounce peroxide (audio) \

Medical Definition of peroxide

: a compound (as hydrogen peroxide) in which oxygen is visualized as joined to oxygen

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More from Merriam-Webster on peroxide

Spanish Central: Translation of peroxide

Nglish: Translation of peroxide for Spanish Speakers

Britannica English: Translation of peroxide for Arabic Speakers Encyclopedia article about peroxide

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