closed book


: something beyond comprehension : enigma

Examples of closed book in a Sentence

the couple's unorthodox marriage is definitely a closed book to those outside of the relationship
Recent Examples on the Web Simply looking at the closed book won't spoil anything. Sam MacHkovech, Ars Technica, 19 Sep. 2022 Alex Steel, the director of teaching strategy and a professor of law at the University of New South Wales, said a number of universities across Australia have announced a move back to closed book exams. Samantha Murphy Kelly, CNN, 19 Jan. 2023 And there’s reason to believe that Kirchick sees this history as a closed book, a chapter that now belongs to the past. Samuel Clowes Huneke, The New Republic, 8 June 2022 Readings of Alwyn as a closed book could be down to him being interviewed by people who aren’t used to encountering his English sensibility. Louis Staples, Harper's BAZAAR, 17 May 2022 Tightly gathered, accordion-like pastry sheets fold neatly onto themselves, resembling the edge of a closed book. Vivian Song, Robb Report, 1 June 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'closed book.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1913, in the meaning defined above

Time Traveler
The first known use of closed book was in 1913

Dictionary Entries Near closed book

Cite this Entry

“Closed book.” Dictionary, Merriam-Webster, Accessed 28 Sep. 2023.

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