metro

Definitions of metro
1

n an electric railway operating below the surface of the ground (usually in a city)

“in Paris the subway system is called the ` metro' and in London it is called the `tube' or the `underground'”
Synonyms:
subway, subway system, tube, underground
Type of:
railroad, railroad line, railway, railway line, railway system
line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight