Subway (5)
'subway' is the definition.
(I know that subway can be written as metro)
This is the entire clue.
(Other definitions for metro that I've seen before include "Parisian underground system" , "Parisian underground railway" , "Urban railway system" , "what moves many Parisians" , "The Paris Underground transport system" .)
'subway' is the definition.
(I know that Underpass is a subway)
This is all the clue.
(Other definitions for underpass that I've seen before include "way below the level of others making progress" , "Tunnel beneath a road" , "way across road?" .)