Thesaurus results for CLOSED BOOKS

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

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Noun

With the capability of observing the cosmos with a wide field of view, Roman will generate first-of-their-kind images to help astronomers explore some of the greatest mysteries, including the unexplained expansion of the universe, according to NASA.

— Eric Lagatta, USA Today, 25 Aug. 2026
And yes, thankfully, that does include taking a visit to a more rural part of the country, where — as any fan of British cozy mysteries will tell you — some of the most interesting murders take place.

— Josef Adalian, Vulture, 25 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

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“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 27 Aug. 2026.

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noun

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