The term "blue book" is typically used to refer to a booklet that contains information, such as prices for goods or a registry of cars. However, there are several synonyms that can be used to mean the same thing. Some alternatives include "catalogue," "manual," "guidebook," or simply "directory." Another term that is often used in the same context is "reference book." This term can be applied to any book that provides information on a specific topic. For example, a reference book on cars might include information on vehicle specifications, prices, and reviews. Regardless of the term used, these types of books are valuable resources for anyone looking to learn more about a particular subject.