One word substitute: A train proceeding from the principal town?

Correct Answer: D. Down-train

The term “down-train” is used to describe a train that is proceeding from the principal or main town in a particular direction. In some railway systems, the term “down” is used to refer to the direction away from the central or originating point. Therefore, a down-train is one that is moving away from the main town or starting point along the railway line.