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 Young, who lives in Connecticut, was unable to pursue a college degree due to her severe fatigue, brain fog, pain, and allergic reactions to most medications. TIME, 16 May 2024 Libra September 23 – October 22 A bad case of brain fog is heading your way. Tarot.com, Baltimore Sun, 8 Mar. 2024 See all Example Sentences for brain fog 

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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brain%20fog. Accessed 31 May. 2024.

Medical 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)
Last Updated: - Updated example sentences
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