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
The buildup of free radicals, called oxidative stress, has been linked to cancer as well as diseases that affect the heart, kidney, brain and respiratory system, according to the Cleveland Clinic.
—
Adrianna Rodriguez, USA TODAY, 6 Feb. 2025
This powder uses quinoa seed extract to minimize the appearance of pores while vitamin C helps protect against free radicals.
—Clare Holden, Glamour, 6 Feb. 2025
Avocado oil reduces unstable harmful molecules (free radicals) in rodent brains and increases the presence of antioxidant molecules.1
6.
—Amy Brownstein, Ms, Rdn, Verywell Health, 31 Jan. 2025
Multiple studies suggest anthocyanin is phenomenal at getting rid of free radicals in the body.
—Rowan Briggs, The Mercury News, 28 Jan. 2025
See all Example Sentences for free radical 
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.
Adrianna Rodriguez, USA TODAY, 6 Feb. 2025
This powder uses quinoa seed extract to minimize the appearance of pores while vitamin C helps protect against free radicals.
—Clare Holden, Glamour, 6 Feb. 2025
Avocado oil reduces unstable harmful molecules (free radicals) in rodent brains and increases the presence of antioxidant molecules.1
6.
—Amy Brownstein, Ms, Rdn, Verywell Health, 31 Jan. 2025
Multiple studies suggest anthocyanin is phenomenal at getting rid of free radicals in the body.
—Rowan Briggs, The Mercury News, 28 Jan. 2025
See all Example Sentences for free radical
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 14 Feb. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share