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 researchers suggest that anthocyanins help reduce a tissue-destroying process called oxidative stress by lowering free radicals in the body.
—
Lauren Manaker Ms, Rdn, Ld, Clec, Verywell Health, 17 Nov. 2023
The synthetic melanin cream soaked up the free radicals and quieted the immune system.
—Laura Baisas, Popular Science, 2 Nov. 2023
Beyond that, artemia salina, or plankton extract, fights free radicals and oxidative stress on the skin.
—Anneke Knot, Peoplemag, 29 Sep. 2023
Meet the Brightening Saffron Serum, which does wonders in terms of minimizing dark spots, free radical protection, and signs of aging such as fine lines.
—Sarah Han, Allure, 9 Nov. 2023
For example: Vegetables: Incorporating vegetables like broccoli, carrots, kale, and spinach can provide important antioxidants that help protect healthy cells from damage caused by free radicals.
—Amber Smith, Discover Magazine, 31 Aug. 2023
In addition to its coverage, the formula is also enhanced with skin-benefiting ingredients, including antioxidant-rich pomegranate extract to keep free radicals at bay and pine bark extract for evening out the skin tone, which is great for dark spots caused by acne blemishes.
—Jessie Quinn, Peoplemag, 26 Oct. 2023
In other words, the metabolism of Modafinil and its analogues shows that in addition to DAT binding, the presence of free radicals in the brain drives sleep and removal of these free radicals may reverse this action.
—Adrafinil.com, The Salt Lake Tribune, 15 Aug. 2023
And no one suspected that the active agent could be nitric oxide, a cancer-causing free radical most often associated with pollution (and not to be confused with nitrous oxide, or laughing gas).
—Clay Risen, BostonGlobe.com, 7 Sep. 2023
See More
Lauren Manaker Ms, Rdn, Ld, Clec, Verywell Health, 17 Nov. 2023
The synthetic melanin cream soaked up the free radicals and quieted the immune system.
—Laura Baisas, Popular Science, 2 Nov. 2023
Beyond that, artemia salina, or plankton extract, fights free radicals and oxidative stress on the skin.
—Anneke Knot, Peoplemag, 29 Sep. 2023
Meet the Brightening Saffron Serum, which does wonders in terms of minimizing dark spots, free radical protection, and signs of aging such as fine lines.
—Sarah Han, Allure, 9 Nov. 2023
For example: Vegetables: Incorporating vegetables like broccoli, carrots, kale, and spinach can provide important antioxidants that help protect healthy cells from damage caused by free radicals.
—Amber Smith, Discover Magazine, 31 Aug. 2023
In addition to its coverage, the formula is also enhanced with skin-benefiting ingredients, including antioxidant-rich pomegranate extract to keep free radicals at bay and pine bark extract for evening out the skin tone, which is great for dark spots caused by acne blemishes.
—Jessie Quinn, Peoplemag, 26 Oct. 2023
In other words, the metabolism of Modafinil and its analogues shows that in addition to DAT binding, the presence of free radicals in the brain drives sleep and removal of these free radicals may reverse this action.
—Adrafinil.com, The Salt Lake Tribune, 15 Aug. 2023
And no one suspected that the active agent could be nitric oxide, a cancer-causing free radical most often associated with pollution (and not to be confused with nitrous oxide, or laughing gas).
—Clay Risen, BostonGlobe.com, 7 Sep. 2023
See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'free radical.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
First Known Use
1870, in the meaning defined above
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. 2023.
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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
Britannica.com: Encyclopedia article about free radical
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