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.
More Miguel Rodriguez/Getty Images What's so mysterious about a team playing well? Jon Vankin, MSNBC Newsweek, 26 July 2025 Years after gaining superpowers from being bombarded by cosmic rays in space, the astronauts-turned-superheroes face a new threat when the mysterious Silver Surfer, Shalla-Bal (Julia Garner), heralds the coming of the world-devouring Galactus (Ralph Ineson). Brian Truitt, USA Today, 26 July 2025 In season 2, John Doe (Mackie) and Quiet enter the Twisted Metal tournament, a sinister demolition derby hosted by a mysterious man known as Calypso (Carrigan). EW.com, 25 July 2025 Meyer, whose previous credits include roles on ABC’s American Housewife and Disney Channel’s Girl Meets World, joined Days of Our Lives in December 2024, playing a mysterious young man who shocked Julie by revealing himself to be her late husband’s estranged grandson. Andy Swift, TVLine, 25 July 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 29 Jul. 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

Last Updated: - Updated example sentences
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