1. closed book - Noun
2. closed book - Adjective
3. closed book - Phrase
something that baffles understanding and cannot be explained
Source: WordNetclosed-book
Her life with others no longer interests him. He wants only her stalking beauty, her theatre of expressions. He wants the minute secret reflection between them, the depth of field minimal, their foreignness intimate like two pages of a closed book. Michael Ondaatje
In a Glasser Quality School there is no such thing as a closed book test. Students are told to get out their notes and open their books. There is no such thing as being forbidden to ask the teacher or another student for help. William Glasser
It has always been a happy thought to me that the creek runs on all night, new every minute, whether I wish it or know it or care, as a closed book on a shelf continues to whisper to itself its own inexhaustible tale. Annie Dillard
We do not believe that the Marxist program, which embodies the continuity of the experience of the actual class struggle and real revolutions of the last one hundred and fifty years, is a definitely closed book. Ernest Mandel
One man's observation is another man's closed book or flight of fancy. Willard van Orman Quine
how it got out is a mystery Source: Internet