a closed book


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a closed book

Someone or something that is difficult to know or understand. She's such a private person that I don't know much about her. I guess she's a closed book. I'm a scientist, so art will always be a closed book to me.
See also: book, closed

a closed book

BRITISH
If something or someone is a closed book to you, you know or understand very little about them. Economics were a closed book to him. He is such a closed book, that guy. Compare with an open book.
See also: book, closed

a closed book

a thing of which you have no knowledge or understanding.
1944 Frank Clune The Red Heart The desert is an open book to the man of the Vast Open Spaces, but to the schoolmaster it was a closed book.
See also: book, closed

a closed ˈbook (to somebody)

a person or a subject that you know nothing about: I’m afraid geophysics is rather a closed book to me.Please let’s not talk about her former life, that’s all a closed book now.
See also: book, closed