Definition of closed book in English:

closed book


  • A subject or person about which one knows nothing.

    ‘accounting has always been a closed book to me’
    • ‘She explained: ‘I still think to this day that there is more to it than what came out but you are dealing with the army and it is a closed book.’’
    • ‘Just how unscrupulous few will ever know, since the murky world of politics is a closed book to most outside observers.’
    • ‘I don't like it, and though I don't consider myself a public person, there is no aspect of my life that is a closed book.’
    • ‘But the whole sweep of history is to her as a closed book.’
    • ‘Publicly men of the left, their private lives were something of a closed book, entry to which was rarely granted.’
    • ‘But when it comes to his emotional life, this period is a closed book.’
    • ‘Hunting, shooting and fishing were a closed book to him along with horse-racing, cricket and sport of any kind, but he would play an occasional game of billiards.’
    • ‘The political parties are closed books as far as the majority is concerned.’
    • ‘Parker remained a closed book to me for some time.’
    • ‘Deadly to explorers, inhospitable to even the mightiest ships and scientific techniques, the vast Southern Ocean has been a closed book to oceanographers until recently.’
    puzzle, enigma, conundrum, riddle, secret, unsolved problem, problem, question, question mark, closed book
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