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
Noun
-
Sign up for Being Human, our newsletter that explores wellness culture, human behavior, mortality and disease, and other mysteries of the body and the mind.—
Helen Ouyang,
The Atlantic,
21 Oct. 2025 -
All these small pleasures that most children know are still mysteries to her.—
Literary Hub,
Literary Hub,
21 Oct. 2025
Noun
-
Check out the all new PLAY hub with puzzles, games and more!—
Chris McKeown,
Cincinnati Enquirer,
25 Oct. 2025
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Check out the all new PLAY hub with puzzles, games and more!—
Amanda Hancock,
Louisville Courier Journal,
24 Oct. 2025
Noun
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Robert surreptitiously attains Alfred’s workbook/diary, where many secrets may exist.—
Kirk Honeycutt,
HollywoodReporter,
20 Oct. 2025
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Set clear boundaries Talk about what's appropriate to share online, and explain that AI chatbots cannot keep secrets or replace human relationships.—
Kurt Knutsson,
FOXNews.com,
19 Oct. 2025
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“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 26 Oct. 2025.
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