<p><strong>Noun</strong></p><ul><li>a passage, hall, or antechamber between the outer door and the interior parts of a house or building.</li><li>Railroads: an enclosed space at the end of a passenger car, serving as a sheltered entrance to the car from another car or from outside the train.</li><li>Anatomy, Zoology: any of various cavities or hollows regarded as forming an approach or entrance to another cavity or space, as that of the internal ear.</li></ul><p><strong>Verb</strong></p><ul><li>to provide with a vestibule.</li></ul>