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open book

noun
1.
someone or something easily understood or interpreted; something very clear:
The child's face is an open book.
Origin of open book
1850-1855
First recorded in 1850-55
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for open book
Contemporary Examples
Historical Examples
  • Margaret sat by the little round table, with an open book before her.

    Henry Dunbar M. E. Braddon
  • He, too, now read the Baron like an open book, and reading him despised him.

    Captain Blood Rafael Sabatini
  • The open book was before her, and the pen was put into her hand.

    The Manxman Hall Caine
  • To him the minds of most men and women he met were as an open book.

    The Doctor of Pimlico William Le Queux
  • I have endeavoured to delineate his character so that it will be as an open book.

    The Girl on the Boat Pelham Grenville Wodehouse
  • In the “study” an open book, face downwards, has been left on a chair.

    They and I Jerome K. Jerome
British Dictionary definitions for open book

open book

noun
1.
a person or thing without secrecy or concealment that can be easily known or interpreted
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Contemporary definitions for open book
noun

something or someone that is easily understandable; something that is very clear; someone who conceals nothing

Examples

Her life is an open book.

Dictionary.com's 21st Century Lexicon
Copyright © 2003-2014 Dictionary.com, LLC
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Idioms and Phrases with open book

open book

Something or someone that can be readily examined or understood, as in His entire life is an open book. This metaphoric expression is often expanded toread someone like an open book, meaning “to discern someone's thoughts or feelings”; variations of this metaphor were used by Shakespeare: “Read o'er the volume of young Paris' face,” (Romeo and Juliet, 1:3) and “O, like a book of sport thou'lt read me o'er” (Troilus and Cressida, 4:5). [ Mid-1800s ]
For an antonym, see closed book
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Difficulty index for open book

Few English speakers likely know this word

Word Value for open

6
8
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