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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Oxidative stress is the imbalance between free radicals (reactive molecules that can damage cells and genetic material) and antioxidants in the body. Lana Barhum, Verywell Health, 31 Oct. 2024 Meet free radicals: unstable oxygen molecules—generated by exposure to external factors like environmental pollution and UV rays—that damage cellular structures like DNA, lipids, and proteins. Abby Dupes, StyleCaster, 20 Sep. 2024 They might be best known as antioxidants (which fend off cell-damaging molecules called free radicals), but newer research suggests they’re also fermented by your friendly gut bacteria, further supporting a healthy microbiome. Erica Sloan, SELF, 4 Sep. 2024 Antioxidants—like curcumin—work by binding to and neutralizing free radicals, thus reducing the risk of cellular damage that can lead to disease. Sarah Bence, Verywell Health, 28 Oct. 2024 See all Example Sentences for free radical 

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 28 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

Last Updated: - Updated example sentences
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