Viscosity

The ratio between the applied shear stress and the rate of shear is called the coefficient of viscosity. This coefficient is a measure of the resistance to flow of the liquid. It is commonly called the viscosity.

The ratio between the applied shear stress and rate of shear of a liquid is called dynamic viscosity.

Kinematic viscosity is a measure of the resistance to flow of a fluid under gravity. It defines the ratio of the viscosity to the density of a liquid.