men·​tal·​ly | \ ˈmen-tᵊl-ē How to pronounce mentally (audio) \

Definition of mentally

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

First Known Use of mentally

15th century, in the meaning defined at sense 1

Keep scrolling for more

Learn More about mentally

Time Traveler for mentally

Time Traveler

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

See more words from the same century

Statistics for mentally

Cite this Entry

“Mentally.” Dictionary, Merriam-Webster, Accessed 16 Jan. 2021.

More from Merriam-Webster on mentally

Nglish: Translation of mentally for Spanish Speakers

Britannica English: Translation of mentally for Arabic Speakers

Comments on mentally

What made you want to look up mentally? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Words of Snow and Ice Quiz

  • image1037863653
  • Which of the following refers to thin, bending ice, or to the act of running over such ice?
True or False

Test your knowledge - and maybe learn something along the way.


Anagram puzzles meet word search.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!