"Wains" are actual wagons with 4-wheels, and Tolkien makes the distinction that the Wainriders had both great Wains and that their nobles rode in great Chariots.
And....
The "Wainriders" of the 19th and 20th centuries
Third Age are not at all the "Easterlings of Rhûn" ruled over by the Nazgûl Khamûl.
The Wainriders were a nomadic people's, while the "Easterlings of Rhûn" hold a static Empire that stretches from the Eastern shores of the Sea of Rhûn into the Far East.
Neither are the Wainriders the Balchoth.... Which are a bit more of a mysterious people (and I have not had time to do the appropriate dissection of their name beyond the "Balch" and "Hoth" which is basically just "Evil hoard").
But Tolkien was never so shallow as to have the initial translation be all there was to a name.
I would need to dig into Sanskrit, Gothic, and Rus languages to determine if anything leapt out.
But.... Back to the subject of this chariot and the Wains, and Wainriders.
This Chariot dates from approximately 2500
Third Age to the War of the Ring, and is a purely "Easterling" Chariot.
I have different designs for the Wainriders, and the Balchoth had no Chariots (they were rejects, who were a bit poor, which is why they invaded Calenardhon to begin with).
And... I have designs for the Wains and the great houses upon them that the Wainriders pulled (based upon early Bulgarians, who did the same thing, and upon Huns and Mongols, who often out yurts on wagons).
But I have yet to move those designs from 2D to 3D.
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