Hydrostatics
From Glossary of Meteorology
hydrostatics
That part of fluid mechanics restricted to fluids in which the velocity (linear or angular) of mass motion does not vary from point to point.
Although the combining form hydro comes from a Greek word meaning water, the term hydrostatic is used for gases as well as liquids. When applied to the atmosphere, hydrostatic equilibrium and hydrostatic pressure logically ought to become aerostatic equilibrium and aerostatic pressure, but these terms are rarely used.
