free radical

noun

Definition of free radical

: 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 Safeguarding skin from free radical damage, reducing inflammation and minimizing the appearance of fine lines and wrinkles are just a few of the precious metal’s perks. Celia Shatzman, Forbes, 2 May 2022 Regular use is guaranteed to reverse the signs of free radical damage and fortify your skin to maintain a youthful glow. Grooming Playbook, The Salt Lake Tribune, 7 Apr. 2022 Top-quality ingredients like glycerin, jojoba oil and esters, macadamia oil, and quinoa extract add enriching protein and protect skin and hair from free radical damage. The Salt Lake Tribune, 29 Mar. 2022 Rich in antioxidants, squalane maintains the skin's moisture barrier, while also offering anti-aging benefits and protection against free radical damage. Emily Belfiore, Travel + Leisure, 27 Mar. 2022 Aloe vera, vitamins A and C, and glycolic and hyaluronic acids work together to soothe, bright, moisturize, and prevent free radical damage. Jasmine Washington, Seventeen, 24 Mar. 2022 Get more sleep Recovering and sleeping at altitude are made more difficult by free radical damage and the thin air. Jeff Gaudette, Outside Online, 3 July 2018 Vitamin C, a water-soluble antioxidant vitamin, plays an important role in maintaining skin health and youthfulness by helping skin to produce more collagen and fighting free radical damage. Kelsey Ogletree, Better Homes & Gardens, 10 Feb. 2022 Kale and spinach are packed with antioxidants, particularly vitamins C and E, which help protect against free radical damage and act as a natural moisturizer. Nicol Natale, Travel + Leisure, 9 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'free radical.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of free radical

1870, in the meaning defined above

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Time Traveler for free radical

Time Traveler

The first known use of free radical was in 1870

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Dictionary Entries Near free radical

freer

free radical

free-range

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Statistics for free radical

Last Updated

8 May 2022

Cite this Entry

“Free radical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/free%20radical. Accessed 21 May. 2022.

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More Definitions for free radical

free radical

noun

Medical Definition of free radical

: 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

Britannica.com: Encyclopedia article about free radical

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