What does the term "viscosity" refer to?

Viscosity refers to the degree of thickness or stickiness of a fluid, indicating how resistant the fluid is to flow. High viscosity means the fluid is thick and flows slowly, such as honey or molasses, while low viscosity indicates a thinner fluid that flows easily, like water or alcohol. This property is crucial in various fields, including physics, engineering, and medicine, as it affects how fluids behave under different conditions. Understanding viscosity helps in predicting how substances interact in different processes, such as in blood flow or the movement of machinery.