It was once said (Winston Churchill, I think) that England and America were peoples (~~~something) seperated by a common language. In my experience, Australia and New Zealand fall into that catagory as well. I have made a fool of myself more times than I can count while in New Zealand.
Colloquial expressions vary from region to region even in one country. I'm from the "deep south", a Boll Weevel is from cotton country, here! Some one from up north would have no idea what a boll weevel even is or where it resides. Try a little further back, to Tex Ritter for a better idea. A Shoo Fly is more contextual and can vary from conversation conversation. In railroading, it refers to a temporary track around a washout. It can mean any number of things from one subject to another. Some funny, some not so funny.
I grasped the concept of kahkis immediately having worked with an engineer from "Taxichusets" for years. No idea how to spell it, just know it when I hear it. Regional colloquialisms have bit more butts than have accents since there were have been different languages.
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