fluidity

American  

[floo-id-i-tee] / fluˈɪd ɪ ti /

noun

fluidities plural

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

Derived Forms

• nonfluidity
  noun

Inflected Forms

Nouns

• fluidities
  plural

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 washes; power blurs as East meets West; metaphor piles onto metaphor.

From New York Times • Aug. 1, 2022

Fluidity helps only in transport of some materials, and does not contribute to the flexibility.

From Textbooks • Jun. 9, 2022

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

From Los Angeles Times • Mar. 1, 2022

It opens the Passages which strain off the Bile; sheaths, or blunts, its Sharpness, gives it a proper Fluidity, prevents its Putridity, and sweetens whatever excessive Acrimony may reside throughout the Mass of Humours.

From Advice to the people in general, with regard to their health by Tissot, S. A. D. (Samuel Auguste David)