closed book


Definition of 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 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 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

Learn More About closed book

Time Traveler for closed book

Time Traveler

The first known use of closed book was in 1913

See more words from the same year

Dictionary Entries Near closed book

closed bolt

closed book


See More Nearby Entries 

Statistics for closed book

Last Updated

12 Jun 2022

Cite this Entry

“Closed book.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon


Test Your Vocabulary

Words Named After People

  • name tags
  • Namesake of the leotard, Jules Léotard had what profession?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!