Pressure

The amount of force acting on a specific amount of surface area, typically measured in pounds per square inch or psi.

Aviation Maintenance Technician Handbook — General, p. G-8

Also defined in 2 more sources

Force per unit area. Hydraulic and pneumatic pressure are normally given in units of pounds per square inch (psi).

Aviation Maintenance Technician Handbook — Airframe, p. G-27

A measure of force applied uniformly over a given unit of surface area.

Aviation Maintenance Technician Handbook — Powerplant, p. G-21

Used throughout the curriculum.