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 With many people complaining about brain fog, attention problems and confusion after COVID-19, researchers are exploring whether infections could have long-term consequences for the brain. Jeanine Santucci, USA TODAY, 31 July 2021 Vang chalks it up to brain fog, a side effect of the pandemic. Kevyn Burger Special To The Star Tribune, Star Tribune, 4 June 2021 And worse yet, among patients who have tested positive for COVID-19, Raimondi notes that the practice has increasingly been seeing worse hygiene among the patients who suffer from long COVID and brain fog. Rachel King, Fortune, 18 Dec. 2021 Stubborn symptoms range from loss of smell or taste to heart or kidney conditions; commonly, people experience excessive fatigue and brain fog. Alison Bowen,, 16 Dec. 2021 The rest of us suffered from asthma, headaches, skin infections, bloody noses and brain fog; my little brother was diagnosed with lead paint poisoning. Harrison Tuttle,, 29 Nov. 2021 The next 48 hours was a mix of dizziness and pain, confusion and a brain fog that Parsons had never experienced before. Tricia Despres,, 18 Nov. 2021 Potential side effects of heroin include dry mouth, heaviness of the arms and legs, nausea, vomiting, and brain fog. Sarah Fielding,, 17 Nov. 2021 My husband had brain fog and fatigue, along with respiratory symptoms. Jennifer Dickman, Time, 2 Nov. 2021

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

Time Traveler

The first known use of brain fog was in 1853

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Dictionary Entries Near brain fog

brain-fever bird

brain fog

brain freeze

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Statistics for brain fog

Last Updated

12 Jan 2022

Cite this Entry

“Brain fog.” Dictionary, Merriam-Webster, Accessed 21 Jan. 2022.

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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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