ALL meanings of standard atmosphere
stand·ard at·mos·phere
S s - noun standard atmosphere an arbitrarily determined vertical distribution of atmospheric pressure, temperature, and density, assumed to have physical constants and conforming to parametric equations, used for calculations in ballistics, the design of pressure altimeters, etc. 1
- noun standard atmosphere a standard unit of atmospheric pressure, having a value of 1013.2 millibars or 29.9213 inches (760 mm) of mercury. 1