What does the prefix "endo-" mean?

The prefix "endo-" means "within." This term is derived from the Greek word "endon," which signifies something that is located inside or within something else. In medical terminology, "endo-" is often used to refer to structures or processes occurring internally. For example, "endocardium" refers to the inner lining of the heart, and "endoscopy" is a procedure used to examine the internal cavities of the body with a flexible camera. Understanding the meaning of this prefix is crucial when interpreting medical terms, as it helps clarify the location or context of anatomical structures and physiological processes.