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.
In The Old Guard 2, following on from the climax of the first film, Andy must come to terms with her newfound mortality while preparing to face a mysterious foe (played by Uma Thurman). Abid Rahman, HollywoodReporter, 1 July 2025 Before long, his life is plagued by a series of mysterious, sinister incidents that threaten to upend his success and bring about a most violent demise. Ryan Lattanzio, IndieWire, 1 July 2025 Two Missouri men already facing charges in the mysterious case of three friends found dead outside a Kansas City home after watching a Chiefs football game last year could have some charges upgraded to include three counts of second degree murder, court documents show. Amanda Musa, CNN Money, 30 June 2025 Still, there are things for franchise diehards to enjoy, including information about the mysterious Section 31 and about the woman who would later call Kirk her baby daddy. Chris Snellgrove, EW.com, 30 June 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 6 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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