mysterious

adjective

mys·​te·​ri·​ous mi-ˈstir-ē-əs 

1

a

: of, relating to, or constituting mystery

the mysterious ways of God

b

: exciting wonder, curiosity, or surprise while baffling efforts to comprehend or identify : mystifying

heard a mysterious noise

a mysterious stranger

a mysterious plane crash

a mysterious illness

2

: stirred by or attracted to the inexplicable

… to help a mysterious wizard … ward off the end of the world with blood sacrifices.

—Robert Houston

mysteriousness noun

Synonyms

• arcane
• cryptic
• deep
• enigmatic
• enigmatical
• impenetrable
• inscrutable
• mystic
• occult
• uncanny

Examples of mysterious in a Sentence

the mysterious ways of nature

We heard a mysterious noise outside our tent.

He died under mysterious circumstances.

A mysterious illness has been spreading through the city.

There's something mysterious about that old woman.

Her behavior was very mysterious.

Recent Examples on the Web

The agent, who leads a double life disguised from her family, is then protected by the mysterious Sam, played by Whishaw. —Max Goldbart, Deadline, 2 Dec. 2024

The mysterious reply sparked a flurry of additional attempts from users on Reddit to get the artificial intelligence tool to say the name – all to no avail. —Eric Lagatta, USA TODAY, 2 Dec. 2024

But the supermassive black holes found in galaxies’ centers, which can be as heavy as billions of suns, are more mysterious and influential. —Jonathan O’Callaghan, WIRED, 1 Dec. 2024

During a red carpet interview at the Australia premiere of Moana 2 in November 2024, Fraser spoke about her mysterious character and echoed the producer's hints that there is more to Matangi than meets the eye. —Samantha Stutsman, People.com, 29 Nov. 2024

Word History

Etymology

mystery entry 1 + -ous, probably after Middle French mysterieux

First Known Use

1578, in the meaning defined at sense 1a

Phrases Containing mysterious

• be mysterious

Kids Definition

mysterious

adjective

mys·​te·​ri·​ous mis-ˈtir-ē-əs 

: containing, suggesting, or presenting a mystery

mysterious noises

also : difficult or impossible to understand

the mysterious ways of nature

mysteriously adverb