The breed of dog called a "German Shepard" in the US is an "Alsatian" in the UK.
The shorter version of Mathematics in the US is "Math" and "Maths" in the UK. Must admit that the UK version makes more sense, given that the term can refer to arithmetic, algebra, geometry, calculus, etc. But I'll never use it. Too late for this old dog to learn new tricks.
I have a vague sense that this number: 1,000,000,000,000 would be a billion in the UK while it is definitely a trillion in the US. (And what we in the US call a billion would be a "thousand millions" in the UK.)
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And FWIW there's doubtless quite a bit of terminology that is incomprehensible outside of a particular region in BOTH countries. Though at least in the US these localisms seem to be dying out. As a kid I remember calling the chocolate stuff you put on ice cream "jimmies," drinking at school from a "water bubbler," and that a sunfish/shiner/bluegill was properly referred to as a "kiver," though whatever it is called it is still absolutely the last kind of freshwater fish you want to catch. In any event in my lifetime they've all gone from common terms in the Boston area to just about extinct. Not sure if that's a good thing or a bad thing, but it is certainly the reality.
Edit to add:League_Girl wrote:
So what do they call lemonade over there? Sprite is a type of pop.
Funny that I should see this. The term "pop" for "soda" isn't at all common around here. If you went into a restaurant in my area and asked "What kind of pop do you have?," I'd bet money you'd have to explain yourself to the server. So maybe local dialects aren't as close to extinction as I thought?
We must have different terms in parts of the USA. Where I live we call it pop or soft drink or beverage or soda.