# airlock

/ˈɛɹˌɫɔk/ (US) · /ˈeəlɒk/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/airlock
Updated: 2026-10-16

## Definition

a small sealed room with a door on each side that lets people move between two places with different air or pressure. You wait inside while one door closes before the other opens.

For teachers: a sealed intermediate chamber fitted with two airtight doors that cannot open at the same time, allowing passage between areas of different pressure or cleanliness while limiting air exchange.

## Examples

- The divers wait inside the airlock before the dive.
- The astronauts enter the airlock to put on their suits before they step out into space.
- Engineers designed the laboratory airlock with interlocking doors that never open together, preserving the sterile environment inside despite constant movement of staff and samples.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.