free radical

noun

: an especially reactive atom or group of atoms that has one or more unpaired electrons
especially : one that is produced in the body by natural biological processes or introduced from an outside source (such as tobacco smoke, toxins, or pollutants) and that can damage cells, proteins, and DNA by altering their chemical structure

Examples of free radical in a Sentence

Recent Examples on the Web When used together, SPF provides a physical barrier between the skin and UV rays, while Vitamin C helps fight off any free radicals that manage to seep through. Jenny Berg, Allure, 24 Oct. 2024 Carotenoids are specifically focused on fighting free radicals that can cause cardiovascular diseases, cancer, and eye diseases. Sara Novak, Discover Magazine, 16 Oct. 2024 The popular serum features 22 plant extracts, including turmeric, which reduces visible signs of aging, sea buckthorn, which fights skin-aging free radicals, Mary’s thistle, which provides nourishment, oat, which tightens, and aloe vera, which soothes. Ali Faccenda, Peoplemag, 18 Sep. 2024 Brightens skin: Arbutin has antioxidant properties that fight skin-damaging free radicals and oxidative stress, helping to improve the appearance of dull or sallow skin. Lindsay Curtis, Verywell Health, 13 Sep. 2024 See all Example Sentences for free radical 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'free radical.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1870, in the meaning defined above

Time Traveler
The first known use of free radical was in 1870

Dictionary Entries Near free radical

Cite this Entry

“Free radical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/free%20radical. Accessed 5 Nov. 2024.

Medical Definition

free radical

noun
: an especially reactive atom or group of atoms that has one or more unpaired electrons
especially : one that is produced in the body by natural biological processes or introduced from outside (as in tobacco smoke, toxins, or pollutants) and that can damage cells, proteins, and DNA by altering their chemical structure

More from Merriam-Webster on free radical

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