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

Through a blend of camellia alba, blue ginger, hyaluronic acid, and vitamins C and E, this antioxidant-rich mist delivers not only a refreshingly cool sensation, but ensures your skin is protected against antioxidants and quenched. — Kiana Murden, Vogue, 21 Aug. 2026

The formula also contains Myrothamnus flabellifolia callus culture extract, an antioxidant-rich plant extract that supports skin recovery, plus adenosine to soften the appearance of fine lines. — Christa Joanna Lee, Allure, 20 Aug. 2026

Eye Health Klinger says arugula contains lutein and zeaxanthin, antioxidants that support eye health. — Embry Roberts, Martha Stewart, 20 Aug. 2026

Signature treatments harness antioxidant-rich wine extracts and oils, while the adults-only sanctuary features 14 treatment rooms, a vitality pool, sauna, steam room, ice therapy and an oceanfront fitness center. — Jill Schildhouse, Forbes.com, 20 Aug. 2026

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