The surrounding pressure; on land, comes from the weight of the atmosphere: at depth, comes from the weight of the water plus the weight of the atmosphere.
The pressure of the air that surrounds the aircraft on the outside.
The atmospheric pressure of the medium surrounding a particular sensor. When no specific information is available, it is assumed to be 14.7 psia.
Adjecent pressure, not necessarily atmospheric, immediately surrounding and influencing an uncompensated pressure actuated switch.
Pressure surrounding the device.
Pressure of the air surrounding a transducer.