closed book

noun

Definition of closed book

: something beyond comprehension : enigma

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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 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 example sentences are selected automatically from various online news sources to reflect current usage of the word 'closed book.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of closed book

1913, in the meaning defined above

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Time Traveler for closed book

Time Traveler

The first known use of closed book was in 1913

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Statistics for closed book

Last Updated

12 Jun 2021

Cite this Entry

“Closed book.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/closed%20book. Accessed 20 Jun. 2021.

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Thesaurus: All synonyms and antonyms for closed book

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