mysterious

adjective

mys·​te·​ri·​ous mi-ˈstir-ē-əs How to pronounce mysterious (audio)
1
a
: of, relating to, or constituting mystery
the mysterious ways of God
b
: exciting wonder, curiosity, or surprise while baffling efforts to comprehend or identify : mystifying
heard a mysterious noise
a mysterious stranger
a mysterious plane crash
a mysterious illness
2
: stirred by or attracted to the inexplicable
… to help a mysterious wizard … ward off the end of the world with blood sacrifices.Robert Houston
mysteriousness noun

Examples of mysterious in a Sentence

the mysterious ways of nature We heard a mysterious noise outside our tent. He died under mysterious circumstances. A mysterious illness has been spreading through the city. There's something mysterious about that old woman. Her behavior was very mysterious.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Nowadays the ghosts of the hotel’s original owner, his wife, and a mysterious child are said to haunt the property. Sophie Friedman, AFAR Media, 22 Oct. 2025 The French fright fest features a very pregnant widow (Alysson Paradis) who sees her home invaded on Christmas Eve by a mysterious woman in black (Beatrice Dalle) dead set on cutting her baby out with some scissors. Brian Truitt, USA Today, 21 Oct. 2025 The short unravels the mysterious aftermath of young boys whose lives have been abruptly taken. Georg Szalai, HollywoodReporter, 21 Oct. 2025 The letter and its mysterious reply were first shared on Reddit by the girl’s parent under the username u/normal-ad2587 on October 13. Melissa Fleur Afshar, MSNBC Newsweek, 21 Oct. 2025 See All Example Sentences for mysterious

Word History

Etymology

mystery entry 1 + -ous, probably after Middle French mysterieux

First Known Use

1578, in the meaning defined at sense 1a

Time Traveler
The first known use of mysterious was in 1578

Browse Nearby Words

Cite this Entry

“Mysterious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mysterious. Accessed 24 Oct. 2025.

Kids Definition

mysterious

adjective
mys·​te·​ri·​ous mis-ˈtir-ē-əs How to pronounce mysterious (audio)
: containing, suggesting, or presenting a mystery
mysterious noises
also : difficult or impossible to understand
the mysterious ways of nature
mysteriously adverb

More from Merriam-Webster on mysterious

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