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

These shifts between stiffness and fluidity play a central role in enabling division.

From Science Daily • Feb. 28, 2026

Leverkusen lacked fluidity but were too good for struggling St Pauli, who have now won just one of their past nine games and sit second-last in the Bundesliga.

From Barron's • Feb. 3, 2026

The direct-address simplicity of the production serves the fluidity of Page’s performance.

From Los Angeles Times • Jan. 17, 2026

The blurred trails emphasise the power and fluidity of the action, while the sharpness of her focused expression adds contrast and intensity.

From BBC • Dec. 25, 2025

He had a looseness and a fluidity that defied physics—imagine a jellyfish if it could walk on land.

From "Born a Crime: Stories from a South African Childhood" by Trevor Noah