mysterious

adjective

mys·​te·​ri·​ous mi-ˈstir-ē-əs 
Synonyms of mysterious
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 …—Robert Houston
mysteriousness noun

Synonyms of mysterious

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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.
This time the central crime revolves around a severed finger that is sent to the high school, and a mysterious — potentially nefarious — new teacher captivating their children. — Seija Rankin, HollywoodReporter, 25 Aug. 2026 Martha-Mary Chapel, Sudbury Reverend Bryce (Toby Huss) presides over the town church, where mysterious ringing bells seem to indicate something dark is afoot. — Nicholas Derenzo, Travel + Leisure, 25 Aug. 2026 Their fledgling relationship has provided a bright spot for droves of fans around the globe who are mourning the death of Shadow's longtime partner, Jackie, following a mysterious illness earlier this month. — Amanda Lee Myers, USA Today, 25 Aug. 2026 The production centers on a voodoo queen and the mysterious happenings in a cemetery. — Todd Martens, Los Angeles Times, 25 Aug. 2026 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

Phrases Containing mysterious

Rhymes for mysterious

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Browse Nearby Words

mysteriosophy
mysterious
mysteriously
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Cite this Entry

“Mysterious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mysterious. Accessed 27 Aug. 2026.

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Kids Definition

mysterious

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