n.1 a an antechamber, hall, or lobby next to the outer door of a building. b a porch of a church etc.
2 US an enclosed entrance to a railway-carriage.
3 Anat. a a chamber or channel communicating with others. b part of the mouth outside the teeth. c the central cavity of the labyrinth of the inner ear.
Derivatives:
vestibular adj.
Etymology: F vestibule or L vestibulum entrance-court