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
Recent Examples on the Web
But her physical discomfort, brain fog, and financial stress had made the idea of writing a novel seem ridiculous.
—
Literary Hub, 30 June 2025
And that’s nothing compared to the sinus pressure, brain fog, and relentless congestion that turns everyday tasks into uphill climbs.
—Tanya Benedicto Klich, Forbes.com, 27 June 2025
Be prepared for keto flu: Understand that temporary side effects like fatigue or brain fog may occur as your body adjusts to burning fat for fuel.12
Experiment with alternatives: Replace some high-carb favorites with low-carb alternatives like cauliflower rice, zucchini noodles, or almond flour.
—Jamie Johnson, Verywell Health, 27 June 2025
Not to mention the risks, more broadly, of getting consistently poor quality or insufficient sleep, like brain fog, mental-health issues, and a not-so-effective immune system, for starters.
—Erica Sloan, SELF, 25 June 2025
See All Example Sentences for brain fog
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Literary Hub, 30 June 2025
And that’s nothing compared to the sinus pressure, brain fog, and relentless congestion that turns everyday tasks into uphill climbs.
—Tanya Benedicto Klich, Forbes.com, 27 June 2025
Be prepared for keto flu: Understand that temporary side effects like fatigue or brain fog may occur as your body adjusts to burning fat for fuel.12
Experiment with alternatives: Replace some high-carb favorites with low-carb alternatives like cauliflower rice, zucchini noodles, or almond flour.
—Jamie Johnson, Verywell Health, 27 June 2025
Not to mention the risks, more broadly, of getting consistently poor quality or insufficient sleep, like brain fog, mental-health issues, and a not-so-effective immune system, for starters.
—Erica Sloan, SELF, 25 June 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 4 Jul. 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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