brain fog


Definition of brain fog

: 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 Health issues like chronic fatigue and brain fog are some of the biggest issues being seen at post-COVID-19 clinics. CBS News, "COVID-19 "long-haulers" share stories of debilitating symptoms: "I will never be the same person"," 5 Jan. 2021 In the year since the coronavirus began spreading across the globe, doctors have noted lingering post-recovery conditions ranging from brain fog and forgetfulness to anxiety, depression, and psychosis. Washington Post, "Large-scale global study to investigate links between covid-19 and cognitive decline," 5 Jan. 2021 Many of them were diagnosed early on in the pandemic and, months later, are still experiencing issues including fatigue, brain fog, confusion, shortness of breath, headaches and/or chest pain. Morgan Romero, oregonlive, "5 Oregonians describe emotional, physical toll of COVID-19: ‘absolutely brutal’," 24 Dec. 2020 There’s also fatigue, cough, shortness of breath, muscle pains, brain fog, mental and emotional disturbances, sleep problems, headaches, loss of taste and smell and others. Pam Defiglio,, "Column: Months after COVID-19, young people worry whether they’ll be able to taste food ever again," 14 Dec. 2020 There’s also new research suggesting that getting enough high-quality leucine may reduce cognitive impairment—sometimes called brain fog—that many people cite as a menopausal symptom. Lindsay Warner, Outside Online, "The Athlete's Guide to Menopause," 8 Dec. 2020 But the conditions surrounding Covid-19 could also make recovery more difficult for people suffering from brain fog. Sara Harrison, Wired, "Confused About Covid Brain Fog? Doctors Have Questions, Too," 6 Nov. 2020 There are brain fog and fatigue, trouble breathing, racing heart beats and neurological symptoms, such as tingling skin. Grace Schneider, The Courier-Journal, "COVID Watch: A return to health for many who have been infected is a long journey," 9 Nov. 2020 But questions remain about what causes brain fog, who is most affected, and how it can be treated. Eve Sneider, Wired, "An Election Week Case Surge, Vaccine Progress, and More Coronavirus News," 6 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'brain fog.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of brain fog

1853, in the meaning defined above

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Time Traveler for brain fog

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The first known use of brain fog was in 1853

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Statistics for brain fog

Last Updated

12 Jan 2021

Cite this Entry

“Brain fog.” Dictionary, Merriam-Webster, Accessed 23 Jan. 2021.

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More Definitions for brain fog

brain fog


Medical Definition of brain fog

: 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), 23 Mar. 2013

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