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

The first known use of closed book was in 1913

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Rhyming Dictionary: Words that rhyme with closed book

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Comments on closed book

What made you want to look up closed book? Please tell us where you read or heard it (including the quote, if possible).


tremendous in size, volume, or degree

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