Poise is the unit of dynamic viscosity. It is named after the French physicist Jean Louis Marie Poiseuille, who made important contributions to the study of fluid mechanics. The dynamic viscosity is a measure of a fluid's resistance to flow when a force is applied to it. It is defined as the ratio of the shear stress to the shear rate of the fluid. The poise is a CGS (centimeter-gram-second) unit of dynamic viscosity, and it is equal to one dyne-second per square centimeter. Another commonly used unit of dynamic viscosity is the Pascal-second (Pa·s) in the SI (International System of Units) system. One poise is equal to 0.1 Pa·s.