Consider this the hand-out (Americanism) to follow the lecture...
It never ceases to amaze me how British people constantly whine about American words and phrases being used here. They frequently do this even when the word/phrase was coined right here in the UK! If it sounds as if it might be American, it is condemned. For instance, at the end of the day, meaning in the final analysis, is British, not American, as many suppose.
British English is awash with Americanisms, as I said earlier, but - what some people seem to be unaware of - there are multitudes of other such words/phrases that we have not adopted. Why the difference? The reason is simple enough...we take on those things which catch our imagination or which enough of us find useful and reject those which don't!
There's no denying that 24/7, for example, is briefer and catchier than all day every day, so we've happily added it to our repertoire. And why not? That's not to say you can't go on saying all day every day if you want to.
Here are ten words and ten phrases created in the USA, most of which I'd be prepared to bet most of us - including yourself, Camioneur - have happily used...
airline, babysitter, checklist, commuter, ditch (abandon), gimmick, high-brow, laser, raincoat, stunt.
Bank on (rely), bark up the wrong tree, hit the headlines, hold down (a job), hold your horses (wait), in the doghouse (in trouble), junk food, pull no punches, stay put, up for grabs.
And that's barely scratching the surface of our debt to Americans' verbal creativity. If you yourself don't like any given coinage such as ball park figure, don't use it, but it is perfectly clear that enough of us do like it, otherwise you wouldn't be seeing/hearing it often enough for it to annoy you.