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

This lightweight, silky formula pairs broad-spectrum sun protection with antioxidant-rich white tea to help fend off free radicals and environmental stressors that can accelerate visible aging. —Christa Joanna Lee, Allure, 12 Sep. 2025

Beet juice has gained popularity among athletes as an antioxidant-rich pre-workout drink. —Stephanie Brown, Verywell Health, 12 Sep. 2025

Follow immediately with the second pad, packed with retinol and antioxidants to boost collagen and calm the skin. —Kiana Murden, Vogue, 12 Sep. 2025

Fresh herbs are often higher in vitamins and antioxidants, especially when added late in the cooking process, better retaining their nutrients. —Katie Rosenhouse, Southern Living, 11 Sep. 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