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
  • Now, after a yearlong delay, an expedition that some believe represents the best chance at solving one of the most enduring mysteries of the 20th century is set to take place this fall.
    — Christopher Cann, USA Today, 12 Aug. 2026
  • That bestselling author of all time whose mysteries make for very good bedtime read-aloud sessions with one’s partner.
    — Literary Hub, Literary Hub, 11 Aug. 2026
Definition of mysteries
Noun
  • Learning new skills, playing word games and having stimulating hobbies like reading or puzzles keeps the mind sharp.
    — Helen Carefoot, Flow Space, 14 Aug. 2026
  • Players can take control of enemies and use their abilities to explore, fight, and solve puzzles, while the creature’s biology changes the world in response to their actions.
    — Matt Gardner, Forbes.com, 12 Aug. 2026
Definition of puzzles
Noun
  • Decades later, her daughter Clara must confront the lingering impact of her family’s scandal and the secrets that have shaped her own life.
    — Kait Hanson, Southern Living, 7 Aug. 2026
  • Remediate exposed secrets continuously Improve hygiene before the breach.
    — Eric Fourrier, Forbes.com, 6 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 15 Aug. 2026.

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