Re: UK - US different word, same meaning
Most if not all of the differences with American English and "original" English stems from the fact that the US had so many European immigrants who brought with them not only their own languages but their own English translations.
In most European countries with a Latin-based language, a holiday for example is a vacation, like in the US and there are many other examples where this is the case, far too many to mention although some have already posted some well-known examples.
All modern languages are evolving all the time and the origins of certain words become blurred or adapted over time too.
Take for example Saudi Arabia. I was there in 1977 and the accepted Arabic word for a car was, phonetically "Seyarra" and probably still is and that came about because the most common vehicle first seen in the Kingdom was called a "Sierra"!!
stevmk2