a student's book or booklet containing problems with spaces for solving them
"The teacher handed out the workbook so students could practice their math problems in writing."
A book, used by a student, in which answers and workings may be entered besides questions and exercises.
"The teacher handed out the math workbook so students could write down their solutions next to each problem."
In plain English: A workbook is a book with spaces for you to write answers and practice what you are learning.
"The teacher handed out workbooks for students to complete their math exercises at home."
Usage: While often associated with school settings, the term applies to any manual containing guided exercises or templates for completing tasks. Do not confuse this physical object with the verb phrase "workbook," which is grammatically incorrect; use only as a noun.
The word workbook is a straightforward combination of the words work and book. It was formed to describe a notebook specifically designed for practicing exercises or completing assignments.