brain fog
noun
: a usually temporary state of diminished mental capacity marked by inability to concentrate or to think or reason clearly
Examples of brain fog in a Sentence
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The authors outline research that shows improvements in these areas can help prevent chronic conditions like osteoporosis and heart disease and manage common menopause symptoms like mood swings, sleep disturbances, brain fog and hot flashes.
—
Helen Carefoot, Flow Space, 30 Oct. 2025
Low iron levels can cause anemia, leading to fatigue, brain fog, and difficulty concentrating.
—Brianna Tobritzhofer, Health, 28 Oct. 2025
The brain, already primed by expectation or anxiety, magnifies those sensations, producing very real pain, bloating, brain fog, fatigue or mood swings.
—New Atlas, 24 Oct. 2025
Kennedy sought the advice of doctors after dealing with severe memory loss and brain fog, reportedly leading to a scan of his brain that showed a dark spot in the imagery.
—Angel Saunders, PEOPLE, 15 Oct. 2025
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Helen Carefoot, Flow Space, 30 Oct. 2025
Low iron levels can cause anemia, leading to fatigue, brain fog, and difficulty concentrating.
—Brianna Tobritzhofer, Health, 28 Oct. 2025
The brain, already primed by expectation or anxiety, magnifies those sensations, producing very real pain, bloating, brain fog, fatigue or mood swings.
—New Atlas, 24 Oct. 2025
Kennedy sought the advice of doctors after dealing with severe memory loss and brain fog, reportedly leading to a scan of his brain that showed a dark spot in the imagery.
—Angel Saunders, PEOPLE, 15 Oct. 2025
See All Example Sentences for brain fog
Cite this Entry
“Brain fog.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brain%20fog. Accessed 3 Nov. 2025.
Copy CitationMedical Definition
brain fog
noun
: a usually temporary state of diminished mental capacity marked by inability to concentrate or to think or reason clearly
This brain fog can be a result of being overly stressed, tired, carrying extra weight, consuming too many calories or consistently consuming a diet poor in nutrients.—Kylie Helgens, The Gazette (Cedar Rapids, Iowa)
Kylie Helgens, The Gazette (Cedar Rapids, Iowa)Love words? Need even more definitions?
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