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

Wild blueberries are an excellent source of vitamins, minerals, and antioxidants, all of which can help support skin, heart, and gut health. —Eleesha Lockett, Verywell Health, 17 Feb. 2026

Turmeric lattes and matcha are tasty beverages loaded with antioxidants and anti-inflammatory compounds that may benefit your long-term health. —Lindsay Curtis, Health, 16 Feb. 2026

The formula also includes antioxidants like vitamin C, vitamin E, and cranberry fruit extract that help to brighten, hydrate, and protect your skin from environmental damage. —Essence Wiley, InStyle, 16 Feb. 2026

Meanwhile, glutathione serves as an antioxidant to brighten skin, while hyaluronic acid draws in water to plump skin on the spot. —Deanna Pai, Vogue, 16 Feb. 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