brain fog


: a usually temporary state of diminished mental capacity marked by inability to concentrate or to think or reason clearly

Example Sentences

Recent Examples on the Web California Fatigue, cough and brain fog. Sandhya Kambhampati, Los Angeles Times, 15 Apr. 2023 And those most common symptoms people complain about, fatigue, devastating fatigue, like can't get out of bed to take a shower kind of fatigue, brain fog, can't remember phone numbers or names. Taylor Wilson, USA TODAY, 14 Mar. 2023 Gibbons, 32, of New York City, had heard it could be used to alleviate symptoms of brain fog. Berkeley Lovelace Jr., NBC News, 4 Feb. 2023 These might include fatigue, difficulty breathing and chest pain, headache and brain fog, digestive problems, and other symptoms like stomach, joint, or muscle pain, per the Centers for Disease Control and Prevention. Brigid Kennedy, The Week, 9 Dec. 2022 Symptoms like those Maxanne had—extreme fatigue, pain, involuntary tremors and spasms, dizziness, brain fog, and general malaise—have persisted throughout history, and medicine has never quite known what to do with them. Natalie Shure, The New Republic, 8 Dec. 2022 Lucas had brain fog, fatigue, and depression. Kaiser Health News, oregonlive, 23 Nov. 2022 Signs of the malady can include breathing problems, brain fog, chronic coughing, changes in taste and smell, overwhelming fatigue, difficulties in performing daily life functions, and disruptions in sleep that can last months, even years, after the infection has cleared the body. Sandee Lamotte, CNN, 18 Sep. 2022 The symptoms are very nonspecific: Anxiety, depression, fatigue, brain fog. Amanda Gokee,, 4 Apr. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'brain fog.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1853, in the meaning defined above

Time Traveler
The first known use of brain fog was in 1853

Dictionary Entries Near brain fog

Cite this Entry

“Brain fog.” Dictionary, Merriam-Webster, Accessed 29 May. 2023.

Medical Definition

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)
Last Updated: - Updated example sentences
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