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
Related Words
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
- mysteriously adverb
- mysteriousness noun
- quasi-mysterious adjective
- quasi-mysteriously adverb
- unmysterious adjective
- unmysteriously adverb
- unmysteriousness noun
Etymology
Origin of mysterious
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 mysterious arson fires in a Hollywood neighborhood started small.
From Los Angeles Times • Apr. 1, 2026
After all, Vance had really just wanted to highlight religion, it would have made a little more sense to portray mysterious flying objects as angels, not demons.
From Salon • Apr. 1, 2026
Yet tourists might find themselves entirely alone at Cromeleque dos Almendres which along with the smaller and less-visited Cromeleque de Vale Maria do Meio are mysterious mini-Stonehenge circles of planted stone monoliths.
From The Wall Street Journal • Mar. 27, 2026
Researchers have uncovered how a mysterious ion channel helps cells break down waste, opening new possibilities for treating Parkinson's disease.
From Science Daily • Mar. 26, 2026
The mysterious massive object was shaped like a barrel topped with a platform and a jumble of structures.
From "The Wild Robot Protects" by Peter Brown
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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.