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

Under Pochettino, the U.S. approach was defined by an aggressive pressing system and tactical fluidity, with the team building from a back-three structure that freed its wing backs to exploit overloads when pushing forward.

From Los Angeles Times • Jul. 12, 2026

ByteDance introduced timeline-based prompting so filmmakers can actually pick specific moments and tweak them, and improved the understanding of camera direction, physics, lighting and fluidity of action.

From Los Angeles Times • Jul. 3, 2026

However it manifests, this sexual fluidity marks something of a “Bi Renaissance,” as Gay Times magazine recently called it.

From The Wall Street Journal • Jun. 14, 2026

“By being called ‘member of technical staff,’ there can be more fluidity of engineers doing more research work, researchers writing more code, or people going in between.

From MarketWatch • May 9, 2026

Something in the way the tennis players hold themselves, or the way they toss the ball, or the fluidity of their motion triggers something in his unconscious.

From "Blink" by Malcolm Gladwell