a closed book


: a person or thing that is difficult to understand
Even to his closest friends, he was always something of a closed book.

Examples of a closed book in a Sentence

Recent Examples on the Web For the folks charged with governing it, OpenAI seems to have been a closed book. Amanda Gerut, Fortune, 31 May 2024

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

Dictionary Entries Near a closed book

Cite this Entry

“A closed book.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/a%20closed%20book. Accessed 24 Jul. 2024.

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