a moving staircase consisting of an endlessly circulating belt of steps driven by a motor, which conveys people between the floors of a public building.
A stairway or incline arranged like an endless belt so that the steps or treads ascend or descend continuously, and one stepping upon it is carried up or down; - originally a trade term, which has become the generic name for such devices. Such devices are in common use in large retail establishments such as department stores, and in public buildings having a heavy traffic of persons between adjacent floors.