Vator

The Vators were the "London Underground" system of Starship UK. They were operated by Winders and/or Smilers.

Children who got a zero in a test were not permitted travel onboard a Vator, they had to walk home. If they tried to ride it they would be sent below, as was Timmy. (DW: The Beast Below)

Vator is likely a contraction for Elevator.