Which term is used to describe a disease of long duration?

The term used to describe a disease of long duration is "chronic." In medical terminology, chronic diseases are characterized by their prolonged course, often lasting for months or even a lifetime. These conditions typically progress slowly and may require ongoing management, rather than being resolved quickly. Chronic diseases include conditions such as diabetes, hypertension, and arthritis, where the focus is often on controlling symptoms and preventing complications over time.

In contrast, acute refers to a condition that arises suddenly and is typically severe in nature, but short-lived. Progressive describes diseases that worsen over time, but does not necessarily refer to their duration. Intermittent indicates that symptoms come and go, rather than being continuously present as seen in chronic conditions. Thus, chronic is the most accurate term to describe a disease that persists over a long period.