enzyme

noun

en·​zyme ˈen-ˌzīm How to pronounce enzyme (audio)
: any of numerous complex proteins that are produced by living cells and catalyze specific biochemical reactions at body temperatures

Examples of enzyme 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.
Proteins are made of amino acids and are needed to build and repair tissues and make important compounds like enzymes and hormones. — Jillian Kubala, HEALTH, 7 Aug. 2026 Martin’s lab has shown that metals can replace biological enzymes in many basic metabolic processes, bolstering the case. — Stephanie Pappas, Scientific American, 7 Aug. 2026 Bananas contain polyphenol oxidase (PPO), an enzyme that can break down polyphenols, which are beneficial for gut, heart and brain health, according to Patrick, who is based in San Diego. — Angelica Stabile, FOXNews.com, 6 Aug. 2026 Nitrous oxide irreversibly disables methionine synthase, the enzyme your body needs to build and maintain the myelin sheath insulating the nerves. — Jesse M. Pines, Forbes.com, 6 Aug. 2026 See All Example Sentences for enzyme

Word History

Etymology

German Enzym, from Middle Greek enzymos leavened, from Greek en- + zymē leaven — more at juice

First Known Use

1881, in the meaning defined above

Time Traveler
The first known use of enzyme was in 1881

Phrases Containing enzyme

Rhymes for enzyme

See All Rhymes for enzyme

Browse Nearby Words

enzymatic
enzyme
enzyme-linked immunosorbent assay
See all Nearby Words

Cite this Entry

“Enzyme.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/enzyme. Accessed 14 Aug. 2026.

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Kids Definition

enzyme

noun
en·​zyme ˈen-ˌzīm How to pronounce enzyme (audio)
: any of various complex proteins produced by living cells that bring about or speed up reactions (as in the digestion of food) without being permanently altered
enzymatic
ˌen-zə-ˈmat-ik
adjective
enzymatically
-ˈmat-i-k(ə-)lē
adverb

Medical Definition

enzyme

noun
en·​zyme ˈen-ˌzīm How to pronounce enzyme (audio)
: any of numerous complex proteins that are produced by living cells and catalyze specific biochemical reactions at body temperatures

More from Merriam-Webster on enzyme

Nglish: Translation of enzyme for Spanish Speakers

Britannica.com: Encyclopedia article about enzyme

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