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

Canned tomatoes are a good source of lycopene, an antioxidant that becomes more bioavailable—meaning easier for the body to absorb—after the cell walls break down during heating. — Bridget Shirvell, Martha Stewart, 7 Aug. 2026

Saffron is rich in antioxidants, which are believed to play a vital role in reducing inflammation and protecting the cells from damage from free radicals. — Bestreviews, Chicago Tribune, 7 Aug. 2026

Garlic Garlic is rich in plant compounds that have anti-inflammatory, antioxidant, and antihypertensive (fighting high blood pressure) properties. — Carrie Madormo, HEALTH, 7 Aug. 2026

Reduces Inflammation Vitamin C, lycopene, lutein, and zeaxanthin are powerful antioxidants that help fight free radicals. — Jamie Johnson, Verywell Health, 5 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