Pressure altitude
The altitude in standard air at which the pressure is the same as that of the existing air. Pressure altitude is read on an altimeter when the barometric scale is set to the standard sea level pressure of 29.92 inches of mercury.
Aviation Maintenance Technician Handbook — Airframe, p. G-27
Also defined in 3 more sources
The altitude in standard atmosphere at which the pressure is the same as the existing pressure.
Aviation Maintenance Technician Handbook — Powerplant, p. G-21
The height above the standard pressure level of 29.92 "Hg. It is obtained by setting 29.92 in the barometric pressure window and reading the altimeter.
Altitude above the standard 29.92 "Hg plane.
Taught in GEN-J Procedures, GEN-J Concepts, GEN-J Quick reference.