The unit of kinematic viscosity in the centimeter-gram-second system. Symbol, St (formerly S). A fluid with a dynamic viscosity of 1 poise and a density of 1 gram per cubic centimeter has a kinematic viscosity of 1 stokes. In SI units, 1 stokes = 1 centimeter squared per second.

According to the current national standard in the United States¹, the stokes is not to be used. Square centimeters per second should be used instead.

The stokes is named for the British physicist, Sir George Gabriel Stokes (1819 – 1903), an early investigator of viscosity² and the founder of the Cambridge school of mathematical physicists.

1. IEEE/ASTM SI 10™-2002.

*American National Standard for Use of the International System of Units (SI): The Modern Metric System.*

New York: IEEE, 30 December 2002.

See Section 3.3.3.

2. For example,

On the theories of the internal friction of fluids in motion and of the
equilibrium and motion of elastic solids.

*Proceedings of the Cambridge Philosophical Society. Mathematical and physical
sciences.*. 1840's

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Last revised: 30 May 2007.