What term describes the resistance to flow of a liquid?

The term that describes the resistance to flow of a liquid is viscosity. Viscosity is a measure of a fluid's internal friction, which affects how easily it flows. A liquid with high viscosity, like honey, flows slowly because its molecules experience greater resistance to movement. In contrast, a liquid with low viscosity, like water, flows more freely due to lower internal friction. Understanding viscosity is crucial in various applications, particularly in climate control and maintenance of ice surfaces, as it impacts how well cooling fluids can move through systems and how they interact with the surfaces they contact.

Density refers to the mass per unit volume of a substance and does not directly relate to the flow characteristics of a liquid. Fluidity is the ability of fluids to flow but it is a broader term and does not specifically address resistance. Capillarity describes the ability of a liquid to flow in narrow spaces without the assistance of external forces, which is a different phenomenon entirely. Hence, viscosity is the appropriate term in this context as it focuses specifically on the resistance to flow.