catalase

noun

cat·​a·​lase ˈka-tə-ˌlās How to pronounce catalase (audio)
-ˌlāz
: a red crystalline enzyme that consists of a protein complex with hematin groups and catalyzes the decomposition of hydrogen peroxide into water and oxygen
catalatic
ˌka-tə-ˈla-tik How to pronounce catalase (audio)
adjective

Examples of catalase 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.
Blood and most of our cells contain an enzyme called catalase. — Dr. Michael Daignault, USA TODAY, 24 Feb. 2022 The job of catalase is to break down hydrogen peroxide, which is harmful to the body in high amounts, into water and oxygen. — Eric Berger, ArsTechnica, 11 Apr. 2025 There are also foods rich in catalase, an enzyme related to the body’s oxidation processes, that can be part of a healthy diet. — Vanessa Santos, Glamour, 9 June 2026 Certain cells in the small intestine have high amounts of catalase, an enzyme that breaks down hydrogen peroxide to release oxygen. — Pratibha Gopalakrishna, STAT, 26 Aug. 2020 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 In the liver 80 percent is broken down by alcohol dehydrogenase; the remaining 20 percent is possibly metabolized by another enzyme, catalase. — Mark Fischetti, Scientific American, 1 Sep. 2023

Word History

Etymology

catalysis

First Known Use

1901, in the meaning defined above

Time Traveler
The first known use of catalase was in 1901

Rhymes for catalase

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Browse Nearby Words

Catalanist
catalase
Çatalca
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Cite this Entry

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

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Medical Definition

catalase

noun
cat·​a·​lase ˈkat-ᵊl-ˌās, -ˌāz How to pronounce catalase (audio)
: a red crystalline enzyme that consists of a protein complex with hematin groups and catalyzes the decomposition of hydrogen peroxide into water and oxygen
catalatic
ˌkat-ᵊl-ˈat-ik How to pronounce catalase (audio)
adjective

More from Merriam-Webster on catalase

Britannica.com: Encyclopedia article about catalase

Last Updated: - Updated example sentences
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