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

Recent Examples of free radical from the Web

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First Known Use of free radical

1870


Medical Dictionary

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

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