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
  • One of the biggest mysteries has been his extreme home/road splits.
    — Maddie Lee, Los Angeles Times, 19 Aug. 2026
  • Now researchers are using advanced imaging technology to look at the narwhal’s tusk in unprecedented detail—studying it in the hope of unraveling some of its mysteries.
    — Jackie Flynn Mogensen, Scientific American, 18 Aug. 2026
Definition of mysteries
Noun
  • Over the years, The Book Rack has offered thousands of books across a wide range of fiction and nonfiction genres, along with candles, notebooks, bookish gifts and more than 100 puzzles.
    — Jessica Alvarado Gamez, Denver Post, 20 Aug. 2026
  • 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
Definition of puzzles
Noun
  • Perhaps fittingly for such a demonized woman, Zosia is giving up her secrets grudgingly.
    — Katie Hunt, CNN Money, 21 Aug. 2026
  • There, a summer of new friends, romance, and family secrets unfolds.
    — Nicole Kliest, Vogue, 21 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 24 Aug. 2026.

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