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
  • The resort also has its own resident marine biologist, Nairika, who works alongside the dive center to help guests better understand the many mysteries of the ocean on their doorstep.
    — Condé Nast, Condé Nast Traveler, 6 Oct. 2026
  • Yet, despite these extraordinary advances, the brain still holds countless mysteries, with much more left to learn and discover and optogenetics has given us a powerful means to take on these challenges.
    — Jackie Flynn Mogensen, Scientific American, 5 Oct. 2026
Definition of mysteries
Noun
  • Unfortunately, Jenna sucks at puzzles, and Christian (who the editors are still not allowing to talk) is great at them.
    — Jason P. Frank, Vulture, 8 Oct. 2026
  • Sign up for The Week's Free Newsletters 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.
    — Irenie Forshaw, TheWeek, 30 Sep. 2026
Definition of puzzles
Noun
  • Mia Wasikowska plays a woman who moves to a remote mansion with her new husband (Tom Hiddleston) and his sister (Jessica Chastain) and discovers the secrets buried in the earth.
    — Brian Tallerico, Vulture, 8 Oct. 2026
  • And that was just the beginning in terms of secrets for their uppity suburban neighborhood.
    — Jackie Strause, HollywoodReporter, 8 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 9 Oct. 2026.

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