The Collaborative International Dictionary of English v.0.48:

Wain \Wain\, n. [OE. wain, AS. w[ae]gn; akin to D. & G. wagen,
   OHG. wagan, Icel. & Sw. vagn, Dan. vogn, and E. way. ????.
   See Way, Weigh, and cf. Wagon.]
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   1. A four-wheeled vehicle for the transportation of goods,
      produce, etc.; a wagon.
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            The wardens see nothing but a wain of hay.
                                                  --Jeffrey.
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            Driving in ponderous wains their household goods to
            the seashore.                         --Longfellow.
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   2. A chariot. [Obs.]
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   The Wain. (Astron.) See Charles's Wain, in the
      Vocabulary.

   Wain rope, a cart rope. --Shak.
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