Dynamic viscosity is also called absolute viscosity in the field of fluid mechanics. Dynamic viscosity is the force required by a fluid to overcome its own internal molecular friction in order for the fluid to flow. In other words, dynamic viscosity is defined as the tangential force per unit area required to move a fluid at a unit velocity in one horizontal plane relative to another, while the molecules of the fluid remain unit distance apart.
Dynamic viscosity is one of the indicators to measure fluid viscosity. Another measure of fluid viscosity is kinematic viscosity.
Viscosity is an important property of fluids used to understand how a fluid behaves and how it moves when in contact with solid boundaries. The viscosity of a fluid is a measure of its resistance to gradual deformation by tensile or shear stress. Shear stress in a fluid is created by intermolecular friction forces exerted as layers of fluid try to slide against each other. Dynamic viscosity is proportional to shear stress and is represented by the symbol, whose SI unit is N s/m2 (Newton seconds per square meter).