Up the mighty Swale!
IN 1984 a horse called Swale won both the Belmont Stakes and the Kentucky Derby. This is the sort of useless information one comes across when researching words. The word, of course, was swale, and Louis Geoffrion, of Lexington in the US, asked how it had achieved its present meaning. He had used it in a memo, saying "progress seems to have plateaued (if not become a swale)", which was queried by a colleague.
(I'd have queried it too, along with plateaued.)
We don't know which dictionary Louis consulted, but the American Heritage Dictionary defines swale as "a low tract of land, especially when moist or marshy, perhaps from Middle English, shade, perhaps of Scandinavian origin; akin to Old Norse svalr, cool.
The Oxford says this derivation relates only to the shade or cool meanings, and of the US low tract of land meaning says "origin unknown". It's a bit difficult to go past the Oxford, but perhaps the AHS is right, in that marshy land does tend to be cool, and low-lying land is often well shaded.
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