mysterious
Americanadjective
-
full of, characterized by, or involving mystery.
a mysterious occurrence.
-
implying or suggesting a mystery.
a mysterious smile.
-
of obscure nature, meaning, origin, etc.; puzzling; inexplicable.
a mysterious inscription on the ancient tomb.
- Synonyms:
- impenetrable, enigmatic, incomprehensible, unintelligible, unfathomable
adjective
-
characterized by or indicative of mystery
-
puzzling, curious, or enigmatic
Synonym Usage
Mysterious, inscrutable, mystical, obscure refer to that which is not easily comprehended or explained. That which is mysterious, by being unknown or puzzling, excites curiosity, amazement, or awe: a mysterious disease. Inscrutable applies to that which is impenetrable, so enigmatic that one cannot interpret its significance: an inscrutable smile. That which is mystical has a secret significance, such as that attaching to certain rites or signs: mystical symbols. That which is obscure is discovered or comprehended dimly or with difficulty: obscure motives.
Other Word Forms
Etymology
Origin of mysterious
Explanation
Something that is mysterious has a secret-like quality that makes it hard to understand or define, like your mysterious answers that made your friends curious about what you were really up to. A dark shadow skims across the surface of lake...a strange disease makes a city's inhabitants violently ill...a large, hairy creature is spotted wandering in the woods. These situations are all mysterious because we don't know their causes. You can see the word mystery in mysterious. A mystery is a hidden or secret thing, so something that is mysterious takes effort to understand, unless it is beyond our comprehension.
Vocabulary lists containing mysterious
Purple Hibiscus
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It's All a Blur: Synonyms for "Unclear"
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Schooled
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The underwater vehicle was coasting about six feet above the ocean floor, two miles deep, when a pinkish, mysterious creature swam into its camera’s sights, drawing gasps in the research vessel floating at the surface.
From Los Angeles Times ● Sep. 5, 2026
Alan Ritchson will pop in as a guest star, as Neagley investigates the mysterious death of an old friend.
From MarketWatch ● Aug. 31, 2026
They argue that the standard interpretation remains intact: a mysterious force known as dark energy is continuing to drive the universe's accelerating expansion.
From Science Daily ● Aug. 29, 2026
This is not an earth-shattering example of the mysterious contours of human desire.
From Salon ● Aug. 20, 2026
Atop the flag lay his Navy sword with a mysterious floral wreath, “To the Memory of Dr. E. K. Kane, from Two Ladies.”
From "American Spirits" by Barb Rosenstock
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.