What is a folk thong anyway?

A point of clarification. Does "cardigan" mean the same thing on both sides of the Atlantic. I mean "jumper" doesn't and nor does "vest."

Ther confusing thing is that the garment Lord Cardigan the Light Brigade chappie was most noted for wearing was a corset. He wore other stuff as well, mind, but I've never seen a picture of him in a cardie. (Or a Liberty Bodice, which I think he'd have seen as very wimpish.)