Words: Wainwright

What exactly is a Wainwright? Someone who makes wains. And what is a Wain? A horse-drawn wagon.
As in this poem by Robert Bridges:

The hazy darkness deepens,
And up the lane
You may hear, but cannot see,
The homing wain.

Here's an interesting article on the origin of Wainwright ("wright", like "wrought", comes from "work") that also explains the derivation of Smith.