Meaning of “book” - Learner’s Dictionary

book

noun uk us /bʊk/
TEXT [ C ]

A1 a set of pages fastened together in a cover for people to read:

a book about animals
Please open your books.
a book of stamps/tickets, etc

a set of stamps, tickets, etc that are fastened together inside a cover

FOR WRITING [ C ]

a set of pages fastened together in a cover and used for writing on:

an address book
→ See also cookery book , take a leaf out of sb's book , phone book , reference book , do sth by the book , be in sb's good/bad books

(Definition of “book noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)