closed book
A person or thing that cannot be easily understood; someone or something incomprehensible or puzzling.
Meaning adapted from Wiktionary, available under CC BY-SA 4.0.
“He is a closed book to me.”
“I have worked with him for years, but he remains a closed book regarding his personal life.”
“Despite her outward friendliness, she remained a closed book, leaving her colleagues to wonder about the true motivations behind her sudden resignation.”
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bad books
Disfavor.
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balance the books
To add up all the debits and credits.
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blot one's copy book
To damage one's own reputation through bad behavior.
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book burning
Any mass destruction, removal, or recalling of books, motion pictures, broadcasts, or electronic works as a form of censorship, especially motivated by religious or political objections to the material.
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book dumping
The practice of donating old used books that burden rather than assist communities.
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book in
To check in (to a hotel).
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call someone every name in the book
To call someone many abusive names.
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close enough for government work
Adequate; acceptable as government work, imperfect but not worth the time nor effort of improving.
Last updated August 10, 2026