The coefficient of viscosity, also known as dynamic viscosity, refers to a fluid's resistance to flow under the influence of an applied force or stress. Synonyms for this term include absolute viscosity, fluid friction coefficient, and shear viscosity. This measure is a critical property of fluids, particularly those used in industrial and engineering applications. It affects the fluid's ability to transfer heat and momentum, and its viscosity can be changed by temperature, pressure, and other variables. Understanding the coefficient of viscosity is crucial for designing systems that involve fluid flow, including pipelines, pumps, and turbines.