wag·on 
(wăgən)
(wăgən)n.
1. A four-wheeled, usually horse-drawn vehicle with a large rectangular body, used for transporting loads.
2.
a. A light automotive transport or delivery vehicle.
b. A station wagon.
c. A police patrol wagon.
3. A child's low, four-wheeled cart hauled by a long handle that governs the direction of the front wheels.
4. A small table or tray on wheels used for serving drinks or food: a dessert wagon.
5. Wagon The Big Dipper
6. Chiefly British An open railway freight car.
tr. & intr.v. wag·oned, wag·on·ing, wag·ons
Idioms: To transport or undergo transportation by wagon.
off the wagon Slang
1. No longer abstaining from alcoholic beverages.
2. No longer persevering with some other program requiring self-discipline, such as losing weight or quitting smoking.
on the wagon Slang
1. Abstaining from alcoholic beverages.
2. Persevering with some other program requiring self-discipline, such as losing weight or quitting smoking.
[Middle English waggin, from Middle Dutch wagen; see wegh- in the Appendix of Indo-European roots.]