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 sisters are openhearted and enjoy revealing ballet’s best-kept secrets, but they have kept a remarkably mysterious online profile.
From Los Angeles Times • Mar. 30, 2026
Ursula has shades of Gellar’s famous characters — Buffy’s physical ferocity, Kathryn Merteuil’s ruthless cattiness, Daphne Blake’s affinity for mysterious games — but doesn’t play to one exclusively.
From Salon • Mar. 26, 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
Every season focuses on one central romance featuring a member of the Bridgerton family - and it's the turn of the reserved and somewhat mysterious Francesca, played by Hannah Dodd.
From BBC • Mar. 24, 2026
So Josie wrote down the phone number of the mysterious kind lady and slid it across the table and said, “This is who your mom should call.”
From "The School for Whatnots" by Margaret Peterson Haddix
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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.