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

Adding vegetables boosts the fiber content and provides antioxidants and other nutrients that support heart health. — Lindsey Desoto, Health, 24 June 2026

The brand says each pack delivers whole veggies, whole fruits, vitamins and minerals, adaptogens, herbs, antioxidants, prebiotics and super mushrooms in one serving. — Samantha Agate, Charlotte Observer, 24 June 2026

Even a 1995 review in Critical Reviews in Food Science and Nutrition described phytic acid as a natural antioxidant tied to lower colon cancer risk and lower cholesterol in animals. — Ryan Brennan, Fort Worth Star-Telegram, 24 June 2026

Blurring bamboo silk powders keep shine in check without dulling skin, while camellia seed oil and antioxidant-rich vitamin E help mature complexions look smooth, hydrated, and naturally luminous. — Christa Joanna Lee, Allure, 23 June 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