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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Five days later, an anonymous caller alerted the Missouri Department of Social Services Children’s Division that Deutsch was allegedly physically and mentally abusing the child. Stephen Sorace, FOXNews.com, 6 Sep. 2026 The woman was said to be mentally ill and emotionally disturbed. Voice Of The People, New York Daily News, 6 Sep. 2026 Her mother was mentally ill, and her struggles, particularly after Steinem’s parents broke up, informed her early understanding on women’s rights. Jason P. Frank, Vulture, 3 Sep. 2026 Those delays ended in 2025, when a Jackson County judge ruled that Scott was mentally competent to stand trial. Ahmed Jawadi, USA Today, 3 Sep. 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 7 Sep. 2026.

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