viscosity

[ vi-skos-i-tee ]

noun

, plural vis·cos·i·ties.

1. the state or quality of being viscous.
2. Physics.
   1. the property of a fluid that resists the force tending to cause the fluid to flow.
   2. the measure of the extent to which a fluid possesses this property.

viscosity

/ vɪsˈkɒsɪtɪ /

noun

1. the state or property of being viscous
2. physics
   1. the extent to which a fluid resists a tendency to flow
   2. Also calledabsolute viscosity a measure of this resistance, equal to the tangential stress on a liquid undergoing streamline flow divided by its velocity gradient. It is measured in newton seconds per metre squared η See also kinematic viscosity specific viscosity

viscosity

/ vĭ-skŏs′ĭ-tē /

1. The resistance of a substance to flow. For example, water has a lower viscosity than molasses and flows more easily. Viscosity is related to the concept of shear force ; it can be understood as the effect of different layers of the fluid exerting shearing force on each other, or on other surfaces, as they move against each other. Viscosity lies behind the skin friction component of drag.
2. ◆ Kinematic viscosity is a measure of the rate at which momentum is transferred through a fluid. It is measured in stokes .
3. ◆ Dynamic viscosity is a measure of the ratio of the stress on a region of a fluid to the rate of change of strain it undergoes. It is equal to the kinematic viscosity times the density of the fluid. It is measured in pascal-seconds or poises .

viscosity

1. The internal friction of a fluid , produced by the movement of its molecules against each other. Viscosity causes the fluid to resist flowing.

Other Words From

• hyper·vis·cosi·ty noun

Word History and Origins

Origin of viscosity¹

First recorded in 1375–1425; late Middle English, from Medieval Latin viscōsitās, from Latin viscōs(us) viscous + -itās -ity

Example Sentences

The end result is a clear, unscented, biodegradable liquid about the viscosity of baby oil that allows you to indulge in a little guilty pleasure without feeling guilty about the environment.

From Los Angeles Times

“Changing the viscosity changes how you experience the flavor,” she said.

From Los Angeles Times

In Review of Scientific Instruments, by AIP Publishing, researchers from the University at Buffalo developed a tool for measuring the viscosity of lava that could increase our understanding of molten rock as well as better improve models of its movement, giving authorities crucial guidance for keeping people safe.

From Science Daily

For fluids like lava, viscosity is the measurement of how fast it flows.

From Science Daily

When a volcano erupts close to human structures, viscosity measurements tell first responders how much time they have to react, and current methods are often insufficient.

From Science Daily