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Definitions

mystery

[mis-tuh-ree, -tree] / ˈmɪs tə ri, -tri /
NOUN
puzzle, secret
Synonyms
STRONGEST
conundrum enigma problem question riddle secrecy subtlety thriller
STRONG
abstruseness charade chiller cliffhanger crux cryptogram difficulty grabber inscrutability mystification occult oracle perplexity poser puzzlement rebus rune sphinx stickler stumper teaser twister whodunit why
WEAK
brainteaser braintwister closed book inscrutableness mindboggler sixty-four thousand dollar question tough nut to crack
Antonyms
WEAK
known understanding

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.

But its provenance had been a mystery, and Alibaba didn’t reveal itself as the developer until Friday.

From The Wall Street Journal • Apr. 10, 2026

Exactly why NIO stock reversed midday is a mystery.

From Barron's • Apr. 9, 2026

True crime and mystery: As with Raymond Chandler, you don’t read “Shadow Ticket” expecting to find out who killed the chauffeur.

From Los Angeles Times • Apr. 9, 2026

Here is where I’m required to offer a throat-clearing assertion that everyone else’s marriage is a mystery, and that we can never know the depths of love or loathing from the outside.

From Salon • Apr. 8, 2026

“You don’t get to define us,” the mystery girl said calmly.

From "The School for Whatnots" by Margaret Peterson Haddix