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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
  • Answering that question would allow astrophysicists to address other mysteries, such as the precise threshold where a neutron star will collapse to form a black hole.
    — Clara Moskowitz, Scientific American, 28 Sep. 2026
  • Here are eight of the best thrillers and mysteries set in the terrifying world of television.
    — L.M. Chilton, PEOPLE, 26 Sep. 2026
Definition of mysteries
Noun
  • Join more than 350,000 subscribers and keep yourself informed with a selection of The Week’s most interesting, enlightening and entertaining stories - plus daily puzzles.
    — Devika Rao, TheWeek, 22 Sep. 2026
  • Little ones can color, solve puzzles, read stories, and more in this booklet.
    — Anja Webb, Parents, 18 Sep. 2026
Definition of puzzles
Noun
  • Curate your own Southeast Florida experience by blending iconic luxury with its local secrets.
    — Condé Nast, Condé Nast Traveler, 23 Sep. 2026
  • Each scene is about secrets, hypocrisy or some form of seduction.
    — Amy Nicholson, Los Angeles Times, 23 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 30 Sep. 2026.

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