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
• fluidness noun
• fluidly adverb
• fluidally adverb
• 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

The jury heard that he said he had stabbed himself in the neck, consumed brake fluid and driven his Porsche car into the water.

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If they are more likely to move, then their homes become available to younger families and the whole market becomes more fluid.

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But here’s the caveat: This is a fluid situation and problems can easily spread to other airports, as officials have already warned.

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Airbus and Boeing, the two biggest aircraft manufacturers, have acknowledged that malfunctions can lead to oil and hydraulic fluid leaking into the engines or power units and vaporizing at extreme heat.

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The virus is spread through blood or other body fluids and can be contracted through something as innocuous as sharing a nail clipper or toothbrush, doctors say.

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Related Words

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