noun / verb
chamber
CHAYM-ber/ˈtʃeɪmbər/
An enclosed space reserved for a particular function.
High windows brighten the spacious, wood-paneled chamber.

Etymology
A word for a vaulted chamber came to mean a room more generally, then other enclosed spaces. The formal-body sense arose by naming an assembly after the room where it met.
In context
it's called the antechamber but a better name is the portcullis chamber because this small space is in fact a security feature
More examples
- The heart has four chambers.
- The upper legislative chamber approves the proposal.
- The soldier checks whether a round is chambered.
Forms
chamber · chambers · chambered · chambering
Similar words
- compartment
- A distinct enclosed section, often within a larger object.
- room
- Usually an enclosed space in a building rather than an organ or machine.