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

Holly Sleppy, a 52-year-old who works at Virtua, shared her frustrations, which many menopausal women are feeling because of a shortage of the estrogen patches used to treat symptoms like hot flashes, irritability and brain fog. —Stephanie Stahl, CBS News, 18 Feb. 2026

Trouble Concentrating Women may feel like their mind is fuzzy, also known as brain fog. —Jocelyn Solis-Moreira, Flow Space, 13 Feb. 2026

Waiting too long can drop your blood glucose (sugar) levels, and low blood sugar may cause tiredness and brain fog. —Christopher Bergland, Verywell Health, 9 Feb. 2026

Lofton stressed that some foods cause the body to become insulin resistant, which can lead to hunger, brain fog, and mental health issues. —Arthur Jones Ii, ABC News, 7 Feb. 2026

Word History

First Known Use

1853, in the meaning defined above

Rhymes for brain fog

• agog
• backlog
• bulldog
• bullfrog
• eclogue
• eggnog
• groundhog
• hedgehog
• leapfrog
• prolog
• sheepdog
• watchdog

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)