The term "rule book" is often used to refer to a set of guidelines or principles that govern a particular activity, organization or system. There are several synonyms that can be used to describe this document, including guidebook, handbook, manual, policy manual, playbook, protocol, code of conduct or code of ethics. These terms offer a more specific reference to the rule book, depending on the context. For instance, "protocol" is mostly used in a formal or diplomatic setting, while "playbook" is more common in sports. In summary, there are various alternatives to the term "rule book", and their usage depends on the specific situation and the audience being addressed.