viscosity

noun

vis·​cos·​i·​ty vi-ˈskä-sə-tē 

plural viscosities

1

: the quality or state of being viscous : a sticky or glutinous consistency

2

a

technical : the property of resistance to flow in any material with fluid properties

… water has a small but measurable viscosity, or "stickiness," which results from the weak mutual attraction of water molecules.

—Hans Christian von Baeyer

b

: the mathematical ratio of the tangential frictional force per unit area to the velocity gradient perpendicular to the direction of flow of a liquid

called also coefficient of viscosity

Synonyms

• consistence
• consistency
• density
• thickness
• viscidity

Examples of viscosity in a Sentence

conducted an experiment to determine the viscosity of motor oil

Recent Examples on the Web

One of the notions that has come out of the conversations around the topic is that the viscosity of cervical mucus may play a role in one's ability to get pregnant. —Fiorella Valdesolo, Vogue, 20 Dec. 2024

The bourbon is smooth and sweet with a noticeable viscosity and mouth weight on the palate. —Joseph V Micallef, Forbes, 17 Dec. 2024

The mixture will have the viscosity of pancake batter. —Jason Mastrodonato, The Mercury News, 16 Dec. 2024

Then, to understand how well the mud flowed, the researchers placed some on a machine called a rheometer that spun the sample and measured its viscosity. —Evan Bush, NBC News, 4 Nov. 2024

Word History

Etymology

Middle English viscosite, from Anglo-French viscosité, from Medieval Latin viscositat-, viscositas, from Late Latin viscosus viscous

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing viscosity

• coefficient of viscosity
• viscosity index

Kids Definition

viscosity

noun

vis·​cos·​i·​ty vis-ˈkäs-ət-ē 

plural viscosities

: the quality or state of being viscous

especially : the characteristic of a fluid that resists flow

an oil of high viscosity

Medical Definition

viscosity

noun

vis·​cos·​i·​ty vis-ˈkäs-ət-ē 

plural viscosities

1

: the quality of being viscous

especially : the property of resistance to flow in a fluid or semifluid

2

: the ratio of the tangential frictional force per unit area to the velocity gradient perpendicular to the direction of flow of a liquid

called also coefficient of viscosity