as in mysteries
something hard to understand or explain
the couple's unorthodox marriage is definitely a closed book to those outside of the relationship
Synonyms & Similar Words
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Example Sentences
Recent Examples of Synonyms for closed books
Noun
-
These are some of life’s great mysteries.—
Hannah Madlener,
Glamour,
24 Apr. 2026 -
Balls and strikes are simple, at least compared to the mysteries of goalie interference.—
Sean McIndoe,
New York Times,
24 Apr. 2026
Noun
-
Check out the all new PLAY hub with puzzles, games and more!—
Kathleen Wong,
USA Today,
29 Apr. 2026
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Apple works at this vertiginous juncture where Emily Dickinson goes rumbling into Etta James and, lately, Beyoncé; where Nico solves puzzles with Randy Newman, Kurt Weill, Nina Simone and the Beatles.—
New York Times,
New York Times,
28 Apr. 2026
Noun
-
Between theater games, fake-blood logistics and a Grim Reaper costume, the teens begin to deal with their secrets and the truth of one fateful night.—
Pam Kragen,
San Diego Union-Tribune,
24 Apr. 2026
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This ancient city still holds so many secrets—these are the best things to do in Athens according to an insider.—
Matt Ortile,
Condé Nast Traveler,
24 Apr. 2026
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Cite this Entry
“Closed books.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/closed%20books. Accessed 1 May. 2026.
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