What term is used to describe a symptom of excessive thirst?

The term that describes a symptom of excessive thirst is polydipsia. This condition often arises when the body is experiencing a loss of fluids or is signaling a need for more hydration. Polydipsia can be a common symptom in certain medical conditions such as diabetes mellitus, where high blood sugar levels lead to increased urination and subsequent fluid loss, triggering the body's thirst response.

Oliguria refers to a condition of producing abnormally small amounts of urine, which does not directly correlate with the sensation of thirst. Dehydration describes a state of the body in which it lacks sufficient water, which may lead to thirst, but it is not specifically the term for the symptom itself. Leukocytosis indicates an elevated white blood cell count, often associated with infection or inflammation, and is unrelated to thirst. Thus, polydipsia is the precise term for the symptom of excessive thirst.