Escalator /(?)/

Es·ca·la·tor

Escalator

n.
  1. 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.