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
  • Ivy must balance the mysteries of Fox Glenn and the White family with threats to her own safety, per the novel’s synopsis.
    — Carly Tagen-Dye, PEOPLE, 15 July 2026
  • The answers to many of the lingering mysteries of the Bermuda Triangle may be explained by the fact that this part of the world is prone to powerful storms.
    — Andrea Romano, Travel + Leisure, 15 July 2026
Definition of mysteries
Noun
  • Providing chew toys for cats along with food puzzles and rotating play options can help channel that energy.
    — Ryan Brennan, Fort Worth Star-Telegram, 15 July 2026
  • Ristroph’s lab frequently addresses these kinds of colorful real-world puzzles.
    — Jennifer Ouellette, ArsTechnica, 13 July 2026
Definition of puzzles
Noun
  • Meanwhile, Gabrielle Union’s favorite gadget, TheraFace’s Depuffing Wand, is on sale too—a worthy recommendation in Union’s Vogue beauty secrets.
    — Conçetta Ciarlo, Vogue, 18 July 2026
  • Among the secrets to her physical fitness and energy is a simple but consistent routine that combines exercise, socializing, and fun.
    — Francesca Martinengo, Vanity Fair, 17 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
See all Nearby Words

Cite this Entry

“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 19 Jul. 2026.

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