closed books

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

Relevance

Example Sentences

Recent Examples of Synonyms for closed books
Noun
  • There are some mysteries we’ll only get answered after death.
    Literary Hub, Literary Hub, 15 Oct. 2025
  • All of these mysteries make TOI-4507 b ripe for follow-up studies.
    Paul Sutter, Space.com, 14 Oct. 2025
Noun
  • Beyond rewriting some rules of physics, the team believes this tiny engine could help tackle one of biology’s biggest puzzles—how proteins fold.
    Alice Gibbs, MSNBC Newsweek, 10 Oct. 2025
  • In other words, this explanation is plausible, but limited in its explanatory power, while simultaneously possessing the drawback of bringing up new puzzles.
    Big Think, Big Think, 9 Oct. 2025
Noun
  • The case raises urgent questions about accountability, national security, and the influence of unelected business figures inside the federal system—and whether Americans have a right to know what secrets they’re being trusted with.
    Robert Alexander, MSNBC Newsweek, 13 Oct. 2025
  • The series follows a Louvre art restorer who uncovers a cursed Mesopotamian mask tied to the storm god Baal Phegor, drawing her into a web of disappearances and dark secrets.
    Ben Croll, Variety, 13 Oct. 2025
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

Cite this Entry

“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 17 Oct. 2025.

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!