(plural green lines)
- A demarcation line, such as that separating Israeli and Palestinian / other Arab territories according to a 1949 armistice, or that separating the Republic of Cyrpus from the Turkish Republic of Northern Cyprus.
- (historical) A German defensive line in Italy during World War II, also known as the Gothic Line.
- An indicator of grammar error in some word processing applications.
- I am getting a green line. Where have I gone wrong?
- Any of the various subway, railway, tram and bus lines around the world marked with color green on the map and/or on the signs along the route or on the vehicles.
- Take the green line towards Wimbledon and get off at East Putney station.