brain fog

American  

[breyn fog, fawg] / ˈbreɪn ˌfɒg, ˌfɔg /

Also brain-fog,

noun

1. a mental state marked by difficulty remembering, concentrating, or thinking clearly, often caused by exhaustion, stress, or illness: For new parents, fatigue and brain fog seem inevitable.

   He had so much brain fog that a single thought felt impossible.

   For new parents, fatigue and brain fog seem inevitable.

   Research has found that long COVID can cause brain fog and memory loss.

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Etymology

Origin of brain fog

First recorded in 1850–55; brain ( def. ) + fog ¹ ( def. )

Example Sentences

Back in November, I posted a note on LinkedIn about brain fog.

From BBC

I dashed it out in about 10 minutes - how for the first time in my 20-year career, I ended up using notes while doing live TV news thanks to the perimenopause brain fog.

From BBC

Or thanking me for "normalising" brain fog.

From BBC

Another woman told me she was reluctant to socialise because she felt unable to follow conversations when thick in the clouds of brain fog.

From BBC

Scores of others shared their own coping strategies: some kept fans on their desks at work to manage hot flushes, others wrote notes to themselves, like I did, to get around the brain fog during meetings and presentations.

From BBC