VISCOSITY

noun (plural -ties) Etymology: Middle English viscosite, from Anglo-French viscosité, from Medieval Latin viscositat-, viscositas, from Late Latin viscosus viscous Date: 14th century the quality or state of being viscous, the property of resistance to flow in a fluid or semifluid, the ratio of the tangential frictional force per unit area to the velocity gradient perpendicular to the direction of flow of a liquid