antioxidant

noun

an·​ti·​ox·​i·​dant ˌan-tē-ˈäk-sə-dənt How to pronounce antioxidant (audio)
ˌan-ˌtī-
: a substance (such as beta-carotene or vitamin C) that inhibits oxidation or reactions promoted by oxygen, peroxides, or free radicals
antioxidant adjective

Examples of antioxidant 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.
Modern-day formulas are often weightless and tout ingredients like hyaluronic acid and antioxidants to plump up the skin and keep it hydrated—while evening out tone and smoothing over textured spots. — Alanna Martine Kilkeary, Glamour, 4 Sep. 2026 And Plums Have Anthocyanins Both cherries and plum skin contain antioxidants called anthocyanins, which give these fruits their dark purple color. — Merve Ceylan, HEALTH, 2 Sep. 2026 These nutritional powerhouses are full of key vitamins, antioxidants and minerals that support overall health. — Helen Carefoot, Flow Space, 31 Aug. 2026 Key Takeaways Saffron and honey both contain powerful antioxidants that can help tackle oxidative stress and reduce inflammation. — Eleesha Lockett, Verywell Health, 30 Aug. 2026 See All Example Sentences for antioxidant

Word History

First Known Use

1919, in the meaning defined above

Time Traveler
The first known use of antioxidant was in 1919

Rhymes for antioxidant

See All Rhymes for antioxidant

Browse Nearby Words

anti-organization
antioxidant
antioxygen
See all Nearby Words

Cite this Entry

“Antioxidant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antioxidant. Accessed 6 Sep. 2026.

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Kids Definition

antioxidant

noun
an·​ti·​ox·​i·​dant ˌant-ē-ˈäk-səd-ənt How to pronounce antioxidant (audio)
ˌan-ˌtī-
: a substance that opposes oxidation or prevents or makes difficult reactions made easier by oxygen

Medical Definition

antioxidant

noun
an·​ti·​ox·​i·​dant ˌant-ē-ˈäk-səd-ənt, ˌan-ˌtī- How to pronounce antioxidant (audio)
: any of various substances (as beta-carotene, vitamin C, and alpha-tocopherol) that inhibit oxidation or reactions promoted by oxygen and peroxides and that include many held to protect the living body from the deleterious effects of free radicals
antioxidant adjective

More from Merriam-Webster on antioxidant

Britannica.com: Encyclopedia article about antioxidant

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