open books

Easy to read

People who are open books conceal nothing—their thoughts, feelings, and intentions are easily read.

The metaphor treats a person as a text available for anyone to examine: She's an open book; you always know exactly what she's thinking.

The phrase often carries approval, suggesting honesty or transparency, though it can also imply naivety or vulnerability.

Opposites
transparency/readability of character

open booksenigmas

Inexplicable mysteries

mysteries · closed books · riddles · puzzles · ciphers

information access/disclosure

open booksclosed books

Unfathomable people or topics

sealed records · classified information · state secrets · black boxes · trade secrets

secrecy/disclosure

open bookssecrets

Concealed information

classified information · hidden depths · stone walls · poker faces

Family

open, books, open book

Familiarity
Top 100,000
Profile
Known to kids · Used worldwide · Timeless · Concrete · Everyday, not technical · Rated G