What is the process of identifying an illness called?

The process of identifying an illness is referred to as diagnosis. This term is derived from the Greek words "dia," meaning through, and "gnosis," meaning knowledge. In the medical field, diagnosis involves a thorough evaluation of the patient's symptoms, medical history, and often, the results of diagnostic tests. The goal is to arrive at a precise conclusion regarding the patient’s condition, which then guides treatment options.

In contrast, the other choices provide different concepts related to health and illness. "Disease" refers to a specific pathological condition characterized by an identifiable group of signs and symptoms. "Symptomology" is the study of symptoms associated with diseases but does not encompass the entire process of identifying an illness. "Prognosis" describes the likely course and outcome of a disease after diagnosis has been made, focusing on the prognosis rather than the identification itself.

Thus, diagnosis is the correct term that directly relates to the process of determining what illness a patient has.