Definition of closed book
: something beyond comprehension : enigma
Examples of closed book
<the couple's unorthodox marriage is definitely a closed book to those outside of the relationship>
First Known Use of closed book
Rhymes with closed book
bankbook, billhook, black book, blue book, boat hook, cant hook, caoutchouc, casebook, chapbook, checkbook, Chinook, codebook, cookbook, daybook, duck hook, e-book, fishhook, gang hook, good book, guidebook, handbook, hornbook, hymnbook, Innsbruck, jump hook, logbook, make book, matchbook, mouth hook, nainsook, nonbook, notebook, outlook, passbook, Pembroke, phrase book, playbook, pothook, prayer book, promptbook, psalmbook, schoolbook, scrapbook, sketchbook, skyhook, songbook, sourcebook, studbook, stylebook, textbook, trade book, unhook, white book, Windhoek, wordbook, workbook, yearbook
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Thesaurus: All synonyms and antonyms for "closed book"
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