depressurize

IPA/diːˈpreʃəraɪz/
KK[dɪprˈɛʃɚˌaɪz]IPA/diːˈpreʃəraɪz/

depressurize — verb

  • depressurizepresent simple I / you / we / they
  • depressurizeshe / she / it
  • depressurizedpast simple
  • depressurizing-ing form

1. to let air out of a sealed space such as a cabin, tank, or chamber so that the a

1.verbtransitive / intransitiveC1
Definition

to let air out of a sealed space such as a cabin, tank, or chamber so that the air inside pushes less hard against its walls

Example

The crew slowly depressurized the cabin before the divers opened the hatch.

transitive: depressurize + the cabin

Sofia turned the valve to depressurize the fuel tank before the repair began.

depressurize + [container] for safe maintenance

Common collocations
  • depressurize the cabin
  • depressurize the tank
  • slowly depressurize
  • depressurize before opening
Synonyms
  • decompress

    near-synonym, more common for diving and medical contexts

  • vent

    stresses letting the gas escape through an opening

Antonyms
  • pressurize

    to raise the air pressure inside instead of lowering it

Grammar Patterns

depressurize + [container/space]

[cabin] + depressurizes

Usage Note

Object is usually a sealed container or space whose contents are held under pressure — a cabin, tank, pipe, or chamber. Frequently passive in technical safety writing.

Common Mistakes

The workers depressurized the gas into the room.
The workers depressurized the tank before opening it.
you depressurize the container, not the gas you release.

Word family

  • pressure
    nounB1
  • pressurize
    verbC1
  • depressurization
    nounC2

Synonym discussion

Sense: verb/1

All three describe lowering pressure, but they fit different scenes. 'Depressurize' is the broad technical term for safely lowering the air pressure inside a sealed cabin, tank, or chamber, and is the word pilots and engineers reach for first. 'Decompress' overlaps heavily but leans toward diving and medicine, where a body or a diver returns slowly to normal pressure: a diver decompresses on the way up. 'Vent' is narrower and more physical — it stresses the gas escaping through a specific opening or valve, so you vent steam from a boiler rather than depressurize it. Choose 'depressurize' for a whole sealed system, 'decompress' for bodies and diving, and 'vent' when the focus is the escaping gas itself.

depressurize ↗decompress ↗vent ↗

Common collocations

Nouns

Adverbs

Phrases

  • depressurize before opening
  • depressurize the cabin

Prepositions

Etymology

LatinOld FrenchEnglish

Built from the prefix 'de-', meaning to remove or reverse, added to the verb 'pressurize'. 'Pressurize' itself comes from 'pressure', which entered English through Old French from the Latin 'pressura', meaning a pressing. The word is modern, appearing in the twentieth century alongside aircraft and spacecraft that needed sealed, pressure-controlled cabins.

First known use

1944

1944, in the meaning defined above