fluid

[floo-id]

noun

1. a substance, as a liquid or gas, that is capable of flowing and that changes its shape at a steady rate when acted upon by a force tending to change its shape.

adjective

1. pertaining to a substance that easily changes its shape; capable of flowing.

2. consisting of or pertaining to fluids.

3. changing readily; shifting; not fixed, stable, or rigid.

   fluid movements.

4. convertible into cash.

   fluid assets.

fluid

/ ˈfluːɪd /

noun

1. a substance, such as a liquid or gas, that can flow, has no fixed shape, and offers little resistance to an external stress

adjective

1. capable of flowing and easily changing shape

2. of, concerned with, or using a fluid or fluids

3. constantly changing or apt to change

4. smooth in shape or movement; flowing

fluid

1. A state of matter, such as liquid or gas, in which the component particles (generally molecules) can move past one another. Fluids flow easily and conform to the shape of their containers.

2. See also state of matter viscosity

fluid

1. In physics, a substance that flows — usually a liquid or a gas.

Other Word Forms

• fluidal adjective
• fluidly adverb
• fluidally adverb
• fluidness noun
• nonfluid noun
• nonfluidly adverb
• unfluid adjective

Word History and Origins

Origin of fluid¹

First recorded in 1595–1605; from Latin fluidus, equivalent to flu(ere) “to flow” + -idus adjective suffix; -id ⁴

Word History and Origins

Origin of fluid¹

C15: from Latin fluidus , from fluere to flow

Synonym Study

See liquid.

Example Sentences

Five goals, four assists, and there is a feeling that football has returned to his body this season - fluid, joyful - after a mixed campaign last time round.

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Verstappen's last remark highlights an issue with the system whereby if the dry ice cannot be kept cold for long enough, the fluid in the system takes on the ambient temperature around the tank.

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"I'm so happy for Mo - he needed that goal. He's been our best offensive player so far. You just see he looked a little bit more fluid."

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While the Free Press has been embraced by conservatives, Weiss has been fluid in her political leanings, at least in the voting booth.

Read more on Los Angeles Times

"Ethan was being beaten, he was being starved, and he was being deprived of fluids," the judge told the court.

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Related Words

• flexible 
• shifting www.thesaurus.com
• unsettled 
• unstable