'A place on a journey'. A sacred piece of ground, sometimes with a temporary shrine building constructed with appropriate rites which serves as the temporary resting-place for the kami who travels out of the main shrine in a mikoshi. Most often the otabisho is the place where the kami resides during a festival (matsuri). Although the main shrine is normally seen as the 'home' of the kami, it is thought that the shrine building may originally have been simply the storage place for the mikoshi while the otabisho was the main ceremonial centre for rites to the kami. During the On-matsuri of the Wakamiya jinja for example the otabisho is at a central place equidistant from the main Buddhist temple and shrine which formed the pre-Meiji jisha complex of Kasuga Daimyojin.
A Popular Dictionary of Shinto. Brian Bocking.