closed books

noun

plural of closed book
as in mysteries
something hard to understand or explain the couple's unorthodox marriage is definitely a closed book to those outside of the relationship

Synonyms & Similar Words

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Example Sentences

Recent Examples of Synonyms for closed books
  1. mysteries
  2. puzzles
  3. secrets
Noun
  • Produced for Arte, the unscripted series, which is set in Paris, Rome, London and New York, sheds light on one of the art world’s greatest mysteries.
    — Ed Meza, Variety, 8 Sep. 2026
  • After five weeks of practices and three preseason games, the Dolphins have solved some of the team’s mysteries, but others have surfaced due to injuries and decisions made this week.
    — Omar Kelly, Miami Herald, 4 Sep. 2026
Definition of mysteries
Noun
  • Central colleague cafes provide complimentary premium coffee and beverages, while gaming lounges with puzzles and tabletop games offer opportunities for hands-on breaks from screens.
    — Charlotte Observer, Charlotte Observer, 4 Sep. 2026
  • With John reluctantly pulled into one of his strangest puzzles yet, the race is on for the Taylors to solve the crime.
    — Lily Ford, HollywoodReporter, 2 Sep. 2026
Definition of puzzles
Noun
  • The new show Sterling Point features a mysterious inheritance, a teen love triangle and deep generational lies and secrets.
    — Brittney Melton, NPR, 4 Sep. 2026
  • Her arrival stirs enough secrets, crushes, and shifting loyalties to fill an eight-episode TV show.
    — Rhoda Feng, New Yorker, 4 Sep. 2026
Definition of secrets
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Browse Nearby Words

closed book
closed books
closed-captioning
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Cite this Entry

“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 11 Sep. 2026.

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