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Synonyms

mysterious

American  
[mi-steer-ee-uhs] / mɪˈstɪər i əs /

adjective

  1. full of, characterized by, or involving mystery.

    a mysterious occurrence.

    Synonyms:
    cryptic, occult, esoteric, secret
  2. implying or suggesting a mystery.

    a mysterious smile.

  3. of obscure nature, meaning, origin, etc.; puzzling; inexplicable.

    a mysterious inscription on the ancient tomb.

    Synonyms:
    impenetrable, enigmatic, incomprehensible, unintelligible, unfathomable

mysterious British  
/ mɪˈstɪərɪəs /

adjective

  1. characterized by or indicative of mystery

  2. puzzling, curious, or enigmatic

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

First recorded in 1610–20; mystery 1 + -ous

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.

Not long after the hack, a mysterious website appeared, inviting journalists to type “Die Sony” into any internet browser, where they could find tens of thousands of leaked emails.

From The Wall Street Journal

MILAN—When a mysterious Russian teenage figure skater showed up at the Olympic ice rink, nobody was quite sure what to expect.

From The Wall Street Journal

With this successful launch, researchers now have new data to examine how these mysterious dark patches fit into the broader auroral circuit.

From Science Daily

Jonah waited until Mom and Dad were out of his room before he tucked the mysterious letter back in his drawer.

From Literature

The lesser character of a mysterious grand design.

From Salon