I
Any liquid or gas that cannot sustain a shearing force when at rest and that undergoes a continuous change in shape (see flow) when subjected to such a stress .
Compressed fluids exert an outward pressure that is perpendicular to the walls of their containers. A perfect fluid lacks viscosity , but real fluids do not.
II
[c mediumvioletred] (as used in expressions)
cerebrospinal fluid
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