A workbook unit is a collection of educational materials that are used to teach a particular LESSON. It typically includes a LESSON plan, worksheets, activities, and other resources. The term 'workbook unit' is often used in the context of language learning, but it can also be used for any subject. The crossword solution for the term 'workbook unit' is LESSON, which is an instruction or set of instructions given to students to help them learn a particular subject.