mys·te·ri·ous | \mis-ˈtir-ē-əs \

Definition of mysterious 

1a : 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

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Other Words from mysterious

mysteriously adverb
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.
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Recent Examples on the Web

Those assets definitely look like Fallout 4 assets, so a full-on Fallout set around the mysterious Vault 76 could be one solution. Hayden Dingman, PCWorld, "Bethesda reveals Fallout 76," 30 May 2018 Their mistakes will seem mysterious to the human eye, and alarming. Aarian Marshall, WIRED, "The Uber Crash Won't Be the Last Shocking Self-Driving Death," 31 Mar. 2018 Just three months before the sighting in Arizona, it was revealed that U.S. Defense Department has been investigating UFOs for years, and videos of Navy pilots sighting mysterious aircraft was released. Grace Donnelly, Fortune, "Pilots from American Airlines and Learjet Spotted a UFO over Arizona in February," 29 Mar. 2018 If a deal is made, Russell will star as a teacher who takes an interest in a mysterious and withdrawn student. Borys Kit, The Hollywood Reporter, "Keri Russell in Talks to Star in Guillermo del Toro-Produced Thriller 'Antlers' (Exclusive)," 11 July 2018 But some become obsessed, longing to know more about something both mysterious and frightening. Joseph P. Laycock, Smithsonian, "A Search for Mysteries and Monsters in Small Town America," 11 July 2018 The best insights into the neurology of our mysterious, extinct relatives came from analyzing the shape and volume of the spaces inside their fossilized skulls. Jon Cohen, Science | AAAS, "Exclusive: Neanderthal “minibrains” grown in dish.," 20 June 2018 Afternoon Once fortified, head for the hills — and perhaps the most powerful and mysterious expression of Chumash culture. Jeanne Cooper, San Francisco Chronicle, "One Day, One Place: First inhabitants offer different view of Santa Barbara," 12 June 2018 The Force moves in mysterious ways, and ultimately, the story isn’t about Rey’s past, but about her future. Jaya Saxena, GQ, "Star Wars: J.J. Abrams Maybe Didn’t Want Rey’s Parents To Be Nobodies," 4 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mysterious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mysterious

1578, in the meaning defined at sense 1a

History and Etymology for mysterious

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

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Phrases Related to mysterious

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Last Updated

11 Oct 2018

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Time Traveler for mysterious

The first known use of mysterious was in 1578

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More Definitions for mysterious



English Language Learners Definition of mysterious

: strange, unknown, or difficult to understand


mys·te·ri·ous | \mi-ˈstir-ē-əs \

Kids Definition of mysterious

: strange, unknown, or hard to understand or explain a mysterious noise a mysterious stranger

Other Words from mysterious

mysteriously adverb She mysteriously disappeared.
mysteriousness noun

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Comments on mysterious

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


a state of commotion or excitement

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