A vestibule (also anteroom, antechamber, outer room, air-lock entry or foyer) is a small room leading into a larger space such as a lobby, entrance hall, or passage, for the purpose of waiting, withholding the larger space from view, reducing heat loss (
air trap, windbreak), providing storage space for outdoor clothing ( mudroom), etc. The term applies to structures in both modern and classical architecture since ancient times.
In antiquity, antechambers were employed as transitional spaces leading to more significant rooms, such as throne rooms in palaces or the naos in temples. In ancient Roman architecture, a vestibule (Latin: vestibulum) was a partially enclosed area between the interior of the house and the street.
