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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But at least his brain fog was lessening, thanks to the enzymes.
—
David Rabe, The New Yorker, 2 Feb. 2025
The agency, in total, has directed $1.8 billion toward studying the disease, which has been linked to extreme fatigue, brain fog, and heart problems.
—Brittney Melton, NPR, 23 Dec. 2024
Hot flashes, night sweats, mood swings, brain fog—this didn’t sound like a party.
—Nell Beram, Allure, 5 Feb. 2025
The common symptoms of POTS include light-headedness, fainting, brain fog, fatigue, headache, blurred vision, tremors, and nausea.
—Daniel R. Depetris, Newsweek, 10 Jan. 2025
See all Example Sentences for brain fog 
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David Rabe, The New Yorker, 2 Feb. 2025
The agency, in total, has directed $1.8 billion toward studying the disease, which has been linked to extreme fatigue, brain fog, and heart problems.
—Brittney Melton, NPR, 23 Dec. 2024
Hot flashes, night sweats, mood swings, brain fog—this didn’t sound like a party.
—Nell Beram, Allure, 5 Feb. 2025
The common symptoms of POTS include light-headedness, fainting, brain fog, fatigue, headache, blurred vision, tremors, and nausea.
—Daniel R. Depetris, Newsweek, 10 Jan. 2025
See all Example Sentences for brain fog
Dictionary Entries Near brain fog
Cite this Entry
“Brain fog.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brain%20fog. Accessed 22 Feb. 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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