1. To maintain normal air pressure in (an enclosure, as an aircraft or submarine).

2. To cause to have or function at greater than normal air or gas pressure: The stairwells are pressurized to prevent smoke from entering during a fire.

3. To put (gas or liquid) under a greater than normal pressure.

4. Informal To subject to psychological, political, or other nonphysical pressure: pressurized the government to enact reforms.