Viscosity Definition

Viscosity and Fluid Flow

You can think of viscosity as a measure of a fluid's rate of flow. Syrup, for example, has a higher viscosity than oil.
You can think of viscosity as a measure of a fluid's rate of flow. Syrup, for example, has a higher viscosity than oil. Huw Jones, Getty Images

Viscosity Definition

Viscosity is the ratio of the magnitude of an applied shear stress to the velocity gradient that it produces.