overground

Meanings

1. Above the ground.
2. Mainstream, not underground.

1. A commuter rail or similar rail transport system, or a train in such systems, generally running through an urban area largely above ground and faster than an underground or metro with fewer stops.

1. simple past and past participle of overgrind

1. The London Overground, a counterpart of London Underground operated by TfL (Transport for London), which operates some of the various lines around London which are mainly above ground.

Etymology

From over- + ground.