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
  • For new discoveries, everyday mysteries, and the science behind the headlines, follow NPR's Short Wave podcast.
    — Will Stone, NPR, 8 July 2026
  • However, even though the JWST has been able to use its MIRI (Mid-Infrared Instrument) and NIRCam (Near-Infrared Camera) to study Centaurus A like never before, there are still mysteries to be solved about this structure.
    — Robert Lea, Space.com, 7 July 2026
Definition of mysteries
Noun
  • Check out the all new PLAY hub with puzzles, games and more!
    — Alexandra Frost, USA Today, 29 June 2026
  • To test that, the final group completed cognitively demanding games such as mazes and shape puzzles called tangrams that contained no academic content.
    — Supreet Kaur, Scientific American, 10 June 2026
Definition of puzzles
Noun
  • Residents are strictly governed by regulations and believe the outside world is toxic, but the protagonist, an engineer named Juliette Nichols, begins to uncover secrets about the Silo’s history and the truth behind their world.
    — Erik Kain, Forbes.com, 4 July 2026
  • Seeking a fresh start, Ellie moves into a house on Delaney Row hoping to leave her troubled past behind, only to discover that her new home is steeped in dark secrets and unsettling mysteries.
    — Kait Hanson, Southern Living, 3 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 10 Jul. 2026.

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