know like a book
In real, traceable use. Part of the curated seed collection; community review is coming.
Meaning · English
To have an extensive and penetrating understanding of (something or someone).
Where it’s used:
Used
American English
Examples
He's a bad man, that John Mason, and my advice to you and to every one, is to keep clear of him. I know him like a book.
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “know like a book” mean?
To have an extensive and penetrating understanding of (something or someone).
Is “know like a book” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.