Flat-foot or splay-foot is that deformity in which there is loss of the arch, and the foot tends to be pronated and abducted.
I mind that you said it was a splay-foot, and here's the explanation.
Though still some traces of our rustic vein And splay-foot verse, remained, and will remain.
And here I thought all along it was because you was splay-foot farmers, and unfortunate, you know, that way like all nesters is.
splayfoot splay·foot (splā'fut')