Plain English Meaning

Airplanes that keep the cabin air thicker than the thin air outside, so people inside can breathe comfortably even when flying very high.

Full Definition

Airplanes equipped with a system that pumps conditioned air into a sealed cabin to maintain a higher internal air pressure than the surrounding atmosphere, allowing occupants to breathe normally while the airplane operates at high altitudes where outside air is too thin to support human function.

Context Anchor

Seen in cabin fire, smoke, oxygen, and high-altitude operating procedures.

Derivation

Pressurized comes from pressure, from the Latin pressura, meaning a pressing or squeezing. The cabin air is, in , pressed in and held at a higher than the outside air.