air lock

US: (âr′lok′)

WordReference Random House Learner's Dictionary of American English © 2026

ˈair ˌlock, n. [countable]

1. Civil Engineering an airtight chamber permitting passage to or from a space in which the air is kept under pressure.

WordReference Random House Unabridged Dictionary of American English © 2026

air′ lock′, 

1. Civil Engineering an airtight chamber permitting passage to or from a space, as in a caisson, in which the air is kept under pressure.
2. Mechanical Engineering the impedance in the functioning of a pump or a system of piping caused by the presence of an air bubble;
   vapor lock.
• 1855–60

air-lock  (âr′lok′), v.t. 

1. to place in or confine to an air lock:
   to air-lock divers before they descend.

• 1855–60