Which combining form refers to disease?

The combining form that refers to disease is "path/o." This prefix is derived from the Greek word "pathos," which means suffering or disease. It is commonly used in medical terminology to denote conditions related to diseases, such as "pathology," which is the study of diseases. Understanding this combining form is crucial for recognizing and interpreting various medical terms related to disease processes and conditions.

The other combining forms relate to specific anatomical structures or systems rather than general disease. For example, "proct/o" refers to the rectum or anus, "rhin/o" pertains to the nose, and "tonsill/o" relates to the tonsils. Each of these forms is important in its own context but does not convey the broad concept of disease that "path/o" embodies.