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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And after several brain health retreats, Six Senses now runs a one-day Mind Your Brain program at several of its properties, from Fiji to the Seychelles, claiming to combat everything from brain fog to mental fatigue with activities like brain games, yoga, sound baths, and meditation.
—
Melinda Fulmer, Robb Report, 11 June 2026
Millions of women are walking into doctors’ offices with fatigue, anxiety and brain fog and walking out with a thyroid prescription or an antidepressant.
—Allison Palmer, Sacbee.com, 10 June 2026
Persistent low energy, irritability, brain fog and apathy toward daily life are the clearest signals that a structured wellness experience could help.
—Hanna Wickes, Charlotte Observer, 10 June 2026
Stories like Martinez’s are fueling interest in HBOT as a treatment for long COVID, a broad constellation of symptoms, including brain fog and debilitating fatigue that affects millions of people worldwide and has no clear remedy.
—Clarissa Brincat, Scientific American, 1 June 2026
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Melinda Fulmer, Robb Report, 11 June 2026
Millions of women are walking into doctors’ offices with fatigue, anxiety and brain fog and walking out with a thyroid prescription or an antidepressant.
—Allison Palmer, Sacbee.com, 10 June 2026
Persistent low energy, irritability, brain fog and apathy toward daily life are the clearest signals that a structured wellness experience could help.
—Hanna Wickes, Charlotte Observer, 10 June 2026
Stories like Martinez’s are fueling interest in HBOT as a treatment for long COVID, a broad constellation of symptoms, including brain fog and debilitating fatigue that affects millions of people worldwide and has no clear remedy.
—Clarissa Brincat, Scientific American, 1 June 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 14 Jun. 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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