fluid


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Related to fluid: fluid mechanics, fluid dynamics, Fluid retention, Newtonian fluid

fluid,

any substance that is able to flow. Of the four states of matterstates of matter,
forms of matter differing in several properties because of differences in the motions and forces of the molecules (or atoms, ions, or elementary particles) of which they are composed.
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, only a solidsolid,
one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from liquid and gas, in which a substance has both a definite shape and a definite volume.
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 is not a fluid, since it has a definite shape that is not readily changed. Any liquidliquid,
one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from solid and gas, in which a substance has a definite volume but no definite shape.
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, gasgas,
in physics, one of the three commonly recognized states of matter, the other two being solid and liquid. A substance in the gaseous state has neither definite shape nor definite volume. Like liquids, gases are fluids and assume the shape of their containers.
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, or plasmaplasma,
in physics, fully ionized gas of low density, containing approximately equal numbers of positive and negative ions (see electron and ion). It is electrically conductive and is affected by magnetic fields.
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 is classed as a fluid.

fluid

[′flü·əd]
(physics)
An aggregate of matter in which the molecules are able to flow past each other without limit and without fracture planes forming.

fluid

1. a substance, such as a liquid or gas, that can flow, has no fixed shape, and offers little resistance to an external stress
2. capable of flowing and easily changing shape
References in classic literature ?
You will tell me that the electric fluid which abounds in the air is the principal cause of this variableness.
My only food consisted of vegetable milk from the plants which gave so bounteously of this priceless fluid.
This fluid mass comprises two billions two hundred and fifty millions of cubic miles, forming a spherical body of a diameter of sixty leagues, the weight of which would be three quintillions of tons.
Enormous quantities of a ruddy-brown fluid were spurting up in noisy jets out of the machine.
Go into my cell as quickly as you can; draw out one of the feet that support the bed; you will find it has been hollowed out for the purpose of containing a small phial you will see there half-filled with a red-looking fluid.
The men scampered in insane fever of haste, racing as if to achieve a sudden success before an exhilarating fluid should leave them.
At first, it lay lightly on the surface of the fluid, appearing to imbibe none of its moisture.
While resting with her foot on the step of the carriage, about to enter it, Julia, whose looks were depressed from shame, saw a fluid that was discoloured with tobacco fall on her shoe and soil her stocking.
A single drop of the cold fluid seemed to freeze every drop of blood in my body; the fever that had been burning in my veins gave place on the instant to death-like chills, which shook me one after another like so many shocks of electricity, while the perspiration produced by my late violent exertions congealed in icy beads upon my forehead.
His dressings were soon applied, and consisted only of some pounded bark, moistened with a fluid that he had expressed from some of the simples of the woods.
As a beginning, D'Artagnan set out in the finest of possible weather, without a cloud in the heavens -- without a cloud on his mind, joyous and strong, calm and decided, great in his resolution, and consequently carrying with him a tenfold dose of that potent fluid which the shocks of mind cause to spring from the nerves, and which procure for the human machine a force and an influence of which future ages will render, according to all probability, a more arithmetical account than we can possibly do at present.
Air's a perfectly elastic fluid," roars George above the tumult.