Definition: Treatise is a book or collection containing the works of one or more authors, often in a single volume. It may also refer to a particular type of written work, such as a "treatise on literature" or "treatise on ethics." A treatise is distinguished from a prose work by its focus and depth of thought. It typically contains a clear argument or thesis that guides the reader through the various sections. The work may also include an introduction, conclusion, and appendices, which provide additional information or commentary. The word 'treatise' comes from Latin and means "book of instruction" or "instruction book." It was originally a term used for writing, but has since been applied to books containing instructions or guidance on something, such as "the treatise on literature." In the context of medicine, a treatment is a course of action for treating a disease or condition. A treatment is usually based on a diagnosis and recommended by a medical professional who has studied the patient's condition. A "treatise" can also refer to an academic work that contains detailed information about a particular subject, such as a book on anatomy or physiology. It may be written in prose but often includes illustrations and diagrams to help illustrate points.