A-Z of British Etiquette
When engaging in conversation, your language choice and vocab can set you apart from the hoi polloi with just a few syllables. There, I said it. A dirty concept in this über-liberal society we’re now in, but it is still true. Use the right words and you can be rest assured you’ll be amongst the Saved when God comes to make his final judgment. This is what Nancy Mitford and Professor Alan S. C. Ross termed ‘U’ and ‘Non-U’, back in the 1950s. The former category being the Upper Classes, and the Non-U being everyone else.
Lavatory/toilet is the most well known of these examples, with the middle classes proclaiming that loo is preferable to either. Lavatory remains top of the tree; loo is permissible, however. It is only a bathroom if it’s got a bath in it, and despite what Uncle Sam et al may say, you’re not really going there to have a rest, so avoid restroom.
The below is by no means a comprehensive list, but a good foundation from which to begin.