What does "overground" mean?

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.

What is a synonym for "overground"?

Common synonyms include: aboveground, aerial, airy, overhead, superterranean.

Overground

adj, name, noun, verb

adj, name, noun, verb ·Rare ·Advanced level

Definitions

Noun

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. London
"The overground is ten minutes walk through the gloom. Anna finds a seat in the third carriage she tries."

Verb

1
simple past and past participle of overgrind form-of, participle, past

Adjective

1
Above the ground. not-comparable
"an overground railway"
2
Mainstream, not underground. not-comparable
"They have plans to carry overground books on gay liberation, and a lot of books from small presses."

Proper Noun

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.
"Yes, it was rather bizarre to make a former underground line into part of a network called London Overground, and at Whitechapel the Overground goes under the Underground. But let's not spoil our happy ending for the East London Line."