vestibule
ves.ti.bule \'ves-t*-.byu:(*)l\ n [L vestibulum] 1a: a passage, hall, or room between the outer door and the interior of a b uilding : LOBBY 1b: an enclosed entrance at the end of a railway passenger car 2: any of various bodily cavities esp. when serving as or resembling an ent rance to some other cavity or space : as 2a: the central cavity of the bony labyrinth of the ear or the parts of the membranous labyrinth that it contains 2b: the part of the left ventricle below the aortic orifice
Webster's English Dictionary