airlock
UK: ˈeəlɒk | US: ˈɛrlɑk
n. a sealed compartment with controlled air pressure, used to prevent air leakage between areas of differing pressure (e.g., in spacecraft or submarines).
n. a device in plumbing or brewing systems to prevent backflow of gases or liquids.
The word "airlock" combines "air" (from Old French air, Latin aer, meaning "atmosphere") and "lock" (from Old English loc, meaning "fastening mechanism"). The term emerged in the early 20th century, originally describing a mechanism to trap or regulate air flow in industrial systems. Its usage expanded with advancements in aviation and space technology, where it became critical for maintaining pressure differentials. The logic is straightforward: an "airlock" literally "locks" air in or out of a space.
The astronauts entered the airlock before their spacewalk.
The submarine's airlock prevents water from flooding the cabin.
Breweries use airlocks to allow CO2 to escape during fermentation.
A malfunction in the airlock caused a pressure drop in the space station.
The laboratory's cleanroom has an airlock to maintain sterility.