A four-wheeled, usually horse-drawn vehicle with a large rectangular body, used for transporting loads. A light automotive transport or delivery vehicle. A station wagon. A police patrol wagon. A child's low, four-wheeled cart hauled by a long handle that governs the direction of the front wheels. A small table or tray on wheels used for serving drinks or food: a dessert wagon. The Big Dipper Chiefly British An open railway freight car. To transport or undergo transportation by wagon. off the wagon Slang No longer abstaining from alcoholic beverages. on the wagon Slang Abstaining from alcoholic beverages.