D defs.my
Entry 2 senses Webster, 1913

Viscosity

/vĭs-käs'-ət-ē/ · Vis·cos·i·ty · IPA /vɪsˈkɑsɪti/
01 n. The quality or state of being viscous.
  1. 1.
    The quality or state of being viscous.
  2. 2.
    A property possessed by a viscous fluid, being a resistance to the forces causing a fluid to flow, caused by interactions between the molecules of the fluid and between the fluid and the walls of the conduit through which it moves; also, a measure of such a property.(Physics)