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
  • However, its growing mysteries nudge it, paradoxically, toward the literal, leaving it with few places to go.
    — Siddhant Adlakha, Variety, 2 Sep. 2026
  • Its survey will produce huge amounts of data and could solve several cosmic mysteries, with potential achievements ranging from understanding dark energy to detecting exoplanets—and finding some things astronomers don’t even know about yet.
    — Mary Randolph, Scientific American, 1 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
  • In kitchens, courtyards, bedrooms and on the streets, women shared jokes, secrets, gestures of care and moments of freedom.
    — PhotoVogue, Vogue, 29 Aug. 2026
  • The smell of freshly ground espresso and incense fills the air, and staff speak to patients in hushed, discreet tones, almost as if discussing state secrets.
    — Christopher Elliott, Forbes.com, 29 Aug. 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 Sep. 2026.

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