British: I'll knock you up in the morning.
American: I'll come by your room tomorrow.
In England, a pencil eraser is a "rubber" and in the U.S., that's slang for a condom. In the U.S., "fanny" mean your backside as in "fanny pack," which the British call a "bum bag." Why? In England, "bum" is slang for your butt while "fanny" refers to ... well, a woman's privates.
One night, a friend wrote out the following phrases, taken from a book on how to talk like a Brit. I gather there's a similar book on how to talk like an Australian. She asked us to read it out loud, phonetically, through slightly clenched teeth:
Wonker noodly sair noffa bot this trooleh mofflis spook!"
So I stumped them with this conversation between two Southern gentlemen:
M R Duks!
A shiny Euro to the first person to translate both of these correctly.
I think the late John Ciardi got it right in the introduction to one of his wonderful browser's dictionaries when he described the root meaning of homo sapiens, homo coming from the Greek humus or clay from which humans were said to have been fashioned by God and sapiens meaning to think. So humans are the clay that thinks. Ciardi went on to point out that humans are not the only animals that appear to have thought processes. Some primates have even shown the ability to make tools, so Ciardi's conclusion was that we should really be called homo locquatious; the clay that speaks. If there is anything that distinguishes us from other animals it must be our ability to constantly invent, use, extend, and adapt language.