siding

1. (rail transport) A second, relatively short length of track just to the side of a railroad track, joined to the main track by switches at one or both ends, used either for loading or unloading freight, storing trains or other rail vehicles; or to allow two trains on a same track to meet (opposite directions) or pass (same direction) (the latter sense is probably an American definition).Examples: "They slept where they could, sometimes in an empty truck on a siding near the station, sometimes in a cart behind a warehouse; [...]"; "Laid out over six square kilometres, Sellafield is like a small town, with nearly a thousand buildings, its own roads and even a rail siding – all owned by the government, and requiring security clearance to visit."