antioxidant

American  

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

noun

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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Etymology

Origin of antioxidant

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

Example Sentences

"If you're taking a high dose antioxidant, you could be diminishing your reproductive fitness and part of the journey toward the bad outcome is going to be the effects on the offspring."

From Science Daily • Mar. 27, 2026

That’s on top of the injections Leite gives herself regularly: NAD+, which she says makes her feel energized and alleviates her brain fog, and glutathione, which is marketed for antioxidant and immune support.

From The Wall Street Journal • Mar. 18, 2026

The ultrasound-assisted process also boosted the honey's levels of phenolic compounds, known for their antioxidant and anti-inflammatory effects.

From Science Daily • Mar. 1, 2026

These components may help enhance antioxidant activity in the body and reduce lipid oxidation, a process associated with oxidative stress.

From Science Daily • Feb. 22, 2026

“Just some antioxidant recipes. Ready for BiPAP and America’s Next Top Model?” she asked.

From "The Fault in Our Stars" by John Green