closed book


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

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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Cite this Entry

“Closed book.” Dictionary, Merriam-Webster, Accessed 5 Jul. 2020.

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Thesaurus: All synonyms and antonyms for closed book

Rhyming Dictionary: Words that rhyme with closed book

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