antioxidant

noun

an·​ti·​ox·​i·​dant ˌan-tē-ˈäk-sə-dənt 

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

Same goes for date syrup, which contains essential minerals like potassium, magnesium, and iron as well as antioxidants and fiber. —Jeanne Ballion, Vogue, 14 July 2025

Cantaloupe is a great source of antioxidants for our dogs, says the American Kennel Club. —Kelsey Monstrola, USA Today, 12 July 2025

The specific strain of cherries contains a high concentration of antioxidants, which soak up unwanted chemical byproducts of the day’s exertions. —Jacob Whitehead, New York Times, 12 July 2025

Krill also has astaxanthin, a potent antioxidant with additional anti-inflammatory benefits, said Dr. David Rizik, an interventional cardiologist at HonorHealth in Arizona. —Deirdre Bardolf, FOXNews.com, 10 July 2025

Word History

First Known Use

1919, in the meaning defined above

Rhymes for antioxidant

• oxidant

Kids Definition

antioxidant

noun

an·​ti·​ox·​i·​dant ˌant-ē-ˈäk-səd-ənt 

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- 

: 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