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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At the same time, my primary care doctor and gynecologist suggested my symptoms — brain fog, fatigue and cognitive changes — were caused by menopause.
—
Shon Lowe, Chicago Tribune, 10 Mar. 2026
For Perssonatti, the disease is more about fatigue, brain fog, word salad, and clumsiness.
—Pamela McLoughlin, Hartford Courant, 10 Mar. 2026
Porzingis was diagnosed with postural orthostatic tachycardia syndrome (POTS) last year, an illness that can cause chronic exhaustion, brain fog, a feeling of illness and other symptoms.
—Joseph Dycus, Mercury News, 8 Mar. 2026
That fluctuation of hormones causes this whole litany of symptoms, like hot flashes, night sweats, brain fog, joint pain, dry skin, brittle hair, hair loss, so many things.
—Tribune News Service, Baltimore Sun, 2 Mar. 2026
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Shon Lowe, Chicago Tribune, 10 Mar. 2026
For Perssonatti, the disease is more about fatigue, brain fog, word salad, and clumsiness.
—Pamela McLoughlin, Hartford Courant, 10 Mar. 2026
Porzingis was diagnosed with postural orthostatic tachycardia syndrome (POTS) last year, an illness that can cause chronic exhaustion, brain fog, a feeling of illness and other symptoms.
—Joseph Dycus, Mercury News, 8 Mar. 2026
That fluctuation of hormones causes this whole litany of symptoms, like hot flashes, night sweats, brain fog, joint pain, dry skin, brittle hair, hair loss, so many things.
—Tribune News Service, Baltimore Sun, 2 Mar. 2026
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 15 Mar. 2026.
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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