an·​ti·​ox·​i·​dant | \ˌan-tē-ˈäk-sə-dənt, ˌan-ˌtī-\

Definition of antioxidant 

: a substance (such as beta-carotene or vitamin C) that inhibits oxidation or reactions promoted by oxygen, peroxides, or free radicals

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Other Words from antioxidant

antioxidant adjective

Examples of antioxidant in a Sentence

Recent Examples on the Web

Sadick recommends looking for one that's rich in antioxidants like vitamin C and E, as well as hyaluronic acid, which can seal in moisture and protect the skin's outer layer from external damage. Devon Abelman, Allure, "Why Koreans Are Ditching Their Famous 10-Step Routines for the Skin-Care Diet," 29 Sep. 2018 While Moringa research is in its infancy, Moringa is reported to be high in antioxidants, might reduce blood sugar levels (important for people with diabetes), could act as an analgesic, lower cholesterol, and more. Nan Sterman,, "Branching out with new crops," 31 May 2018 High in antioxidants, blueberries also contain vitamins C and K, and manganese. Allison Horton, miamiherald, "Want to reduce your odds of getting cancer? Stay active, lose weight and eat healthy," 25 May 2018 The boost in antioxidants also helps my skin’s natural defense against sun damage. Mia Adorante Christiansen, Bon Appetit, "5 Ways to Get Your Skin as Psyched About Spring as You Are," 3 May 2018 Rich in antioxidants, the beet has a vivid hue that signals the nutrients inside. Molly Kimball,, "Hard to beat beets for nutrition, so let's learn to love them," 20 Mar. 2018 And the darker the chocolate (which is higher in antioxidants), the better. Susan Selasky, charlotteobserver, "Make your own chocolate bowls for Valentine’s Day," 13 Feb. 2018 Having said that, products containing antioxidants can also be helpful in preventing damage caused by free radicals and other environmental threats. Lauren Valenti, Marie Claire, "The 10 Best Eye Creams for Every Age," 14 Mar. 2017 Vitamin C Everyone touts vitamin C for its abilities to ward off colds and flu, but this potent antioxidant may also improve skin's texture and appearance. Amy Capetta, Woman's Day, "5 Anti-Aging Supplements That May Actually Work," 16 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antioxidant.' 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 antioxidant

1919, in the meaning defined above

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Last Updated

12 Dec 2018

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The first known use of antioxidant was in 1919

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English Language Learners Definition of antioxidant

: a substance that is added to food and other products to prevent harmful chemical reactions in which oxygen is combined with other substances


an·​ti·​ox·​i·​dant | \ˌant-ē-ˈäk-səd-ənt, ˌan-ˌtī- \

Medical Definition of antioxidant 

: 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

Other Words from antioxidant

antioxidant adjective

More from Merriam-Webster on antioxidant

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

Comments on antioxidant

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a soft lustrous wool fabric with mohair

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