1. A four-wheeled vehicle for the transportation of goods, produce, etc.; a wagon. The wardens see nothing but a wain of hay. (Jeffrey) Driving in ponderous wains their household goods to the seashore. (Longfellow)
2. A chariot. The Wain.
(Science: astronomy) See Charles's Wain, in the vocabulary. Wain rope, a cart rope.
Origin: OE. Wain, AS. Waegn; akin to D. & G. Wagen, OHG. Wagan, Icel. & Sw. Vagn, Dan. Vogn, and E. Way. See Way, Weigh, and cf. Wagon.