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
  • There’s much still to learn about this meteorite’s mysteries, says Anya Udry, a planetary scientist at the University of Nevada, Las Vegas, who was not involved with the Science study.
    — Mary Randolph, Scientific American, 29 Oct. 2026
  • An unassuming spinster settled in the English countryside, the majority of Miss Marple's mysteries have taken place right in her own backyard.
    — Kat Chen, Condé Nast Traveler, 27 Oct. 2026
Definition of mysteries
Noun
  • In addition to books, each engagement station features puzzles and toys that help develop motor skills.
    — Rick West, Chicago Tribune, 27 Oct. 2026
  • Players must solve puzzles using the camera to try to break the cycle of madness.
    — Todd Spangler, Variety, 26 Oct. 2026
Definition of puzzles
Noun
  • His new film, which centers on secrets in a renowned vineyard uncovered, slow-burn-style, by a worker and wine critic, aims to land in the $3-$5 million range and potentially attract some even bigger-name talent.
    — Steven Zeitchik, HollywoodReporter, 29 Oct. 2026
  • The Soviet Union, for instance, gained nuclear weapons in part by penetrating the Manhattan Project; more recently, China stole secrets related to the F-22 and F-35 stealth fighter jets and the C-17 cargo plane.
    — Sam Mullins, Foreign Affairs, 28 Oct. 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 5 Nov. 2026.

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