standard atmosphere

noun

1. 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.
2. a standard unit of atmospheric pressure, having a value of 1013.2 millibars or 29.9213 inches (760 millimeters) of mercury.

Example Sentences

As defined by Encyclopedia Britannica, a calorie is "the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius."

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