peroxidase

noun

per·​ox·​i·​dase pə-ˈräk-sə-ˌdās How to pronounce peroxidase (audio)
-ˌdāz
: an enzyme that catalyzes the oxidation of various substances by peroxides

Examples of peroxidase 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.
The horseradish peroxidase reaction’s byproduct then turns the solution red. — IEEE Spectrum, 5 June 2014 The microneedle surface is coated with a thin layer of gold, mixed with a bio-hydrogel composed of biocompatible and hydrophilic chitosan and horseradish peroxidase enzymes. — Mack Degeurin, Popular Science, 19 Mar. 2025 The defense relies on hydrogen peroxide, hydroquinone and a suite of highly specialized enzymes, namely catalases and peroxidases. — Scott Travers, Forbes.com, 21 Apr. 2026 Antioxidant enzymes like glutathione peroxidase in selenium help protect liver cells from damage by reducing unstable oxygen molecules. — Devineé Lingo, M.s., Rdn, Health, 9 Sep. 2024 This polyphenol not only gives turmeric its bright yellow color but also combats free radicals and boosts the body's defense system by activating antioxidant enzymes like superoxide dismutase and glutathione peroxidase. — Lana Barhum, Verywell Health, 13 May 2026 Erythrocyte reduced glutathione levels, erythrocyte glutathione peroxidase and superoxide dismutase activities were significantly increased in the rats kept in the pyramid as compared to the other two groups. — Ncbi Rofl, Discover Magazine, 22 Feb. 2012 Brazil nuts Brazil nuts are one of the richest natural sources of selenium, a trace mineral essential for the production of glutathione peroxidase, a powerful antioxidant enzyme that helps neutralize free radicals and reduce oxidative stress. — Lauren Manaker, SELF, 4 Mar. 2026

Word History

First Known Use

1900, in the meaning defined above

Time Traveler
The first known use of peroxidase was in 1900

Rhymes for peroxidase

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Browse Nearby Words

perovskite
peroxidase
peroxidate
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Cite this Entry

“Peroxidase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/peroxidase. Accessed 7 Jul. 2026.

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Medical Definition

peroxidase

noun
per·​ox·​i·​dase pə-ˈräk-sə-ˌdās, -ˌdāz How to pronounce peroxidase (audio)
: an enzyme occurring especially in plants, milk, and white blood cells and consisting of a protein complex with hematin groups that catalyzes the oxidation of various substances by peroxides

More from Merriam-Webster on peroxidase

Britannica.com: Encyclopedia article about peroxidase

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