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
There is also considerable evidence that alcohol can trigger the body to release harmful molecules called free radicals.
—
Pranoti Mandrekar, The Conversation, 7 Apr. 2025
When enough oxidizing molecules, also called free radicals, show up as an unavoidable byproduct of cells using energy, KEAP1 gets deactivated.
—Lauren Leffer, Popular Science, 27 Mar. 2025
Oxidative stress is an imbalance in the body of unstable molecules called free radicals and antioxidants.
—Emily Kay Votruba, EverydayHealth.com, 12 Mar. 2025
The antioxidant ingredient can also help to protect the skin against free radical damage and wrinkles according to a study.
—Rosa Jisoo Pyo, Vogue, 28 Mar. 2025
See All Example Sentences for free radical
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Pranoti Mandrekar, The Conversation, 7 Apr. 2025
When enough oxidizing molecules, also called free radicals, show up as an unavoidable byproduct of cells using energy, KEAP1 gets deactivated.
—Lauren Leffer, Popular Science, 27 Mar. 2025
Oxidative stress is an imbalance in the body of unstable molecules called free radicals and antioxidants.
—Emily Kay Votruba, EverydayHealth.com, 12 Mar. 2025
The antioxidant ingredient can also help to protect the skin against free radical damage and wrinkles according to a study.
—Rosa Jisoo Pyo, Vogue, 28 Mar. 2025
See All Example Sentences for free radical
Cite this Entry
“Free radical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/free%20radical. Accessed 22 Apr. 2025.
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