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
  • Just bearing witness to the marketing for all these murder-mysteries is enough to make any discerning viewer desperate for Hollywood to hurry up and start chasing the next trend already.
    — Ben Travers, IndieWire, 29 July 2026
  • The anime merely depicts a border spat between a few small nations, whereas the manga is more global in reach and also deals with much of the underlying mysteries of the corrupted world the characters now live in.
    — Ollie Barder, Forbes.com, 29 July 2026
Definition of mysteries
Noun
  • Take along complete puzzles in good condition to trade for something new from the collection.
    — Eric E. Harrison, Arkansas Online, 29 July 2026
  • There are also plenty of games and activities for sale in the hotel store, including watercolor kits, colorful punch balloons, activity books, knitting kits, pick-up sticks, puzzles, toys, and more.
    — Condé Nast, Condé Nast Traveler, 28 July 2026
Definition of puzzles
Noun
  • Forced into an uneasy cohabitation, the two navigate a sweet yet morally complex web of secrets and survival.
    — Hannah Abraham, Forbes.com, 1 Aug. 2026
  • China could be hoping to glean technology secrets from Japanese companies.
    — Jessie Yeung, CNN Money, 31 July 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 3 Aug. 2026.

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