fluidity

American  

[floo-id-i-tee] / fluˈɪd ɪ ti /

noun

1. the quality or state of being fluid.

2. Physics.

   1. the ability of a substance to flow.

   2. a measure of this ability, the reciprocal of the coefficient of viscosity.

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fluidity British  

/ fluːˈɪdɪtɪ /

noun

1. the state of being fluid

2. physics the reciprocal of viscosity

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Other Word Forms

• nonfluidity
  noun

Etymology

Origin of fluidity

First recorded in 1595–1605; fluid + -ity

Explanation

Fluidity is a quality of being graceful or flowing, like the fluidity of a dancer's movements. Things that move with easy, smooth motions have fluidity — think of clouds moving across the sky on a windy day, or the way a modern dancer's body moves. This adjective can also mean "changeable," like the fluidity of ideas being exchanged during a high school debate class. As a physical quality, you might also describe the fluidity of any substance that's fluid, or behaves like a liquid.

Example Sentences

Fluidity in midfield, which is something Jones has spoken about and is something he has tried to address with the likes of Harvey Knibbs and Sonny Carey coming in.

From BBC • Aug. 7, 2025

Fluidity allows greater flexibility to the cell and motion of membrane components required for transport.

From Textbooks • Jun. 9, 2022

Fluidity of gesture, intonation and blocking allow for greater dramatic velocity.

From Los Angeles Times • Mar. 1, 2022

Fluidity is why Walz and state educational leaders earlier this summer mandated that schools plan for three back-to-school scenarios: in-person classes, distance learning and hybrid scenarios.

From Washington Times • Aug. 3, 2020

Fluidity is not the usual state of society.

From Catastrophe and Social Change Based Upon a Sociological Study of the Halifax Disaster by Prince, Samuel Henry