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The poise is the unit of dynamic viscosity in the centimetre–gram–second system of units (CGS). It is named after Jean Léonard Marie Poiseuille. The centipoise is more commonly used than the poise itself. Dynamic viscosity has dimensions of f o r c e × t i m e / a r e a , that is, [ M 1 L − 1 T − 1 ] . The analogous unit in the International System of Units is the pascal-second (Pa⋅s): The poise is often used with the metric prefix centi- because the viscosity of water at 20 °C is almost exactly 1 centipoise. A centipoise is one hundredth of a poise, or one millipascal-second (mPa⋅s) in SI units. The CGS symbol for the centipoise is cP. The abbreviations cps, cp, and cPs are sometimes seen. Liquid water has a viscosity of 0.00890 P at 25 °C at a pressure of 1 atmosphere.