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
Derived 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.
Or is it simply about “trauma and the mysterious workings of the unconscious,” as New York Times critic Beatrice Loayza says?
From Salon • Jun. 8, 2026
Last summer, a NASA-funded asteroid impact warning system detected a mysterious object speeding through the solar system.
From Los Angeles Times • Jun. 6, 2026
His 2011 album, “Smoke Ring for My Halo,” brought him a wider audience, and at this point his music was slightly mysterious, his voice heavily treated with reverb.
From The Wall Street Journal • Jun. 2, 2026
Astronomers have traced a mysterious type of repeating cosmic signal to an unusual pair of stars, providing the strongest evidence yet for the source of one of astronomy's most puzzling phenomena.
From Science Daily • Jun. 2, 2026
She thought of the mysterious howling sound that they had faintly heard from some hidden place behind the wall.
From "The Hidden Gallery" by Maryrose Wood
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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.