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

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

These molecules react with free radicals, effectively neutralizing them, and there’s generally a balance of both in living organisms. —Tom Hawking, Popular Science, 24 Oct. 2024

This essential nutrient protects against cell-damaging free radicals and supports healthy eyes, skin, immunity, and brain function. —Alessandra Signorelli, Vogue, 18 Oct. 2024

Cannabis also contains antioxidants to help protect the skin from damage caused by free radicals and environmental stressors. —Tribune Content Agency, The Mercury News, 2 Oct. 2024

Word History

First Known Use

1870, in the meaning defined above

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