I want to know if I use, for example, a word from american english in Britain or a word from british english in USA they will understand, I say this because there are words that is totally different.
e.g. Flashlight and Torch; Elevator and Lift; Trash Can and Dustbin; Truck and Lorry.
They will understand or they will ask you. Not a problem. Brits get by in North America and vice versa.
There are not many words which are so country specific that English speakers from other countries wouldn’t recognise. I think most people coming to New Zealand would have trouble with the amount of Maori words which are mixed in with English i.e the whanau association. Most of the English words I have trouble understanding from the US and Canada are mainly slang.
With all that said, I think due to Hollywood the British are a little more familiar with North American terminology than we are with there’s. But like Steve and Nathan said it’s not a big enough difference to matter. I think that people normally feel European and Brazilian Portuguese have bigger differences and they’re more than mutually understandable.
We Brits will either understand you or else we will ask you what the phrase means…unless it sounds rude…like bum or fanny pack…don’t go there!