1
: in the mind
Mentally he promised himself that he would never again use a collar on any living creature.Brian Jacques
: using the mind
able to mentally calculate large sums
2
: with regard to the mind or its capacity
physically and mentally healthy people
a mentally competent adult
a mentally challenging activity
… if you try to hide the fact that you feel mentally inadequate, and so go around making jokes about your own dullness and acting as if it didn't bother you at all …David Foster Wallace
I felt too hungry and tired and mentally overloaded to ask any more questions.Rick Riordan

Examples of mentally in a Sentence

Recent Examples on the Web
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The lack of sleep and lack of rest wears down firefighters physically and mentally; the mental alertness, the mental sharpness is not always there, and also the burnout. Rashad Williams, CBS News, 31 July 2026 Heartbreak and rejection leave people emotionally vulnerable, and the manosphere pitch often comes paired with benign advice about standing up for yourself, being mentally tough, or becoming physically active. Adam Serwer, The Atlantic, 28 July 2026 Obviously there is tremendous benefit to an organization when its workforce is mentally healthy and emotionally resilient. Mark C. Perna, Forbes.com, 28 July 2026 Still, the Dodgers could benefit from at least another third-string option at the physically and mentally demanding position. Maddie Lee, Los Angeles Times, 27 July 2026 See All Example Sentences for mentally

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of mentally was in the 15th century

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Cite this Entry

“Mentally.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mentally. Accessed 5 Aug. 2026.

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