antioxidant

American  

[an-tee-ok-si-duhnt, an-tahy-] / ˌæn tiˈɒk sɪ dənt, ˌæn taɪ- /

noun

antioxidants plural

1. Chemistry. any substance that inhibits oxidation, as a substance that inhibits oxidative deterioration of gasoline, rubbers, plastics, soaps, etc.

2. Biochemistry. an enzyme or other organic substance, as vitamin E or beta carotene, that is capable of counteracting the damaging effects of oxidation in animal tissues.

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adjective

1. Chemistry. of or relating to an antioxidant.

antioxidant British  

/ ˌæntɪˈɒksɪdənt /

noun

1. any substance that retards deterioration by oxidation, esp of fats, oils, foods, petroleum products, or rubber

2. biology a substance, such as vitamin C, vitamin E, or beta carotene, that counteracts the damaging effects of oxidation in a living organism

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antioxidant Scientific  

/ ăn′tē-ŏk′sĭ-dənt,ăn′tī- /

1. A chemical compound or substance that inhibits oxidation. Certain vitamins, such as vitamin E, are antioxidants and may protect body cells from damage caused by the oxidative effects of free radicals.

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Other Word Forms

Noun Inflected Forms

• antioxidants
  plural

Etymology

Origin of antioxidant

First recorded in 1925–30; anti- + oxidant ( oxid(ize) + -ant )

Explanation

An antioxidant is a substance that helps prevent damage caused by certain chemical reactions in our bodies. Fruits, vegetables, and beans are full of antioxidants. Vitamins C and E are familiar antioxidants found in foods like spinach, strawberries, kiwifruit, and lima beans. These substances work in two main ways. They sometimes prevent chemical oxygen reactions that produce damaging, unstable free radicals. They can also bind with the free radicals to make them stable and keep them from causing damage. Antioxidants don't just protect our bodies; they are also used to keep food fresh — a squeeze of lemon juice (Vitamin C) on a sliced apple helps prevent oxidation that turns the fruit brown.

Example Sentences

Antioxidant preservatives serve a different purpose, helping to prevent oxidation so foods do not become brown or rancid.

From Science Daily • Jun. 18, 2026

In my recipe for Super Antioxidant Blueberry Smoothie, I’ve combined them with pomegranate juice, yogurt and a little honey.

From Seattle Times • Jul. 1, 2023

Antioxidant levels inside tissues increase, protecting against damage caused by sudden changes in the amount of oxygen in cells.

From Science Magazine • Jun. 21, 2023

Antioxidant activity and composition of M&M's plain peanut candy.

From Salon • Jan. 22, 2023

I was interested in the benefits of chocolate and I said: "Antioxidant."

From "Counting by 7s" by Holly Goldberg Sloan