For our Dutch friends:

  • Tapping the side of the forehead in the UK means you are stupid, not smart.  But we love the Dutch, so you'll get away with it.
  • Also, you will give yourself away by inanely giggling at the fire extinguishers on the London Underground that say LUL on them.
  • The Dutch accent and word choices can amuse the British. Make the most of it and get preferential treatment!

Most American/Canadian travellers will be aware of certain words having different meanings, but just in case: -

  • Do not talk about fanny packs here! It will cause sniggering and some personal embarassment on your behalf. Here, they are "bum bags". (The reason is that in UK English, a 'fanny' refers to the female reproductive parts). A "bum" is a bottom, posterior or rump, not a tramp or homeless person.
  • "Fag" is a slang word for cigarette, though can be used by the gay community or in referring to a homosexual male, usually in a pejorative manner.
  • Suspenders for trousers may be referred to as "braces", although these are falling out of fashion...
  • "Braces" are also metal wire contraptions used in orthodontics;
  • To 'wash up' means 'to do the dishes'
  • Jaguar is pronounced jag-yu-ar not jag-war;
  • Herbs not "erbs"
  • To most, "pants" in UK means what "panties" does in the US.  Trousers is an adequately fine description.
  • Do not use the word 'ignorant' to descibe someone as uninformed on a subject. Here, it implies intentional ignorance and is an insult.
  • Need a washcloth/face cloth? Ask for a flannel.
  • Aluminium = al-you-min-ee-um and NOT al-oo-min-um 
  • Tomato = to-mah-toe NOT toe-may-doh
  • Lieutenant is pronounced leff-tenant (though loo-tenant is slowly gaining ground amongst the youth, and is technically more correct).
  • To 'get pissed' is to be heavily under the influence of alcohol and not to be annoyed (which is expressed as 'pissed off').
  • 'Taking the p*ss' describes someone poking fun at another person.
  • When ordering food, it's better to say "Could I have" instead of "Could I get", although people will understand you.
  • When ordering beer don't just ask for "a beer". There are three main types - lager (light beer), bitter or ale and many varieties of each.  If the choice is too much, ask the bar staff what they recommend.

Place name pronunciation guide (let's face it, us British love to complicate matters): 

Leicester = Lester, Warwickshire= Warickshuh (similarly, Warwick = Warick), Gloucestershire = Glosstershuh (similarly Gloucester = Glosster) Bicester = Bistuh, Loughborough= Luff-bruh, Beaulieu = Byoolee (and not the Francophonic pronunciation, boh-lee-yuh), Edinburgh - Edin-bruh (not Edin-burrow or any other dipthongic concoction) and Norwich = Norr-itch.

The British also 'swallow' the '-ha' of place names ending '-ham' eg Durham, Nottingham, Birmingham, Cheltenham, Tottenham are sounded, Dur'um, Notting'um, Birming'um, Chelt'num, Tott'num, respectively.

It should be noted that while, in England, the "shire" in the names of counties is pronounced shuh, in Scotland and Wales, it usually rhymes with fire. Also, not all county names end with -shire, Devon is Devon and not Devonshire, unless you happen to be discussing the Duke of Devonshire, which is quite unlikely. It's like calling Florida Floridastate or Texas Texasstate. It sounds silly and is wrong!

In conclusion:

The above is, of course, an exercise in semantic pedantry (as well as sounding remarkably like something you'd hear on Monty Python or Fawlty Towers).  Most people in the UK enjoy talking to visitors and will not make a big issue about different meanings of certain words.

Only a very rude person or someone 'taking the p*ss' would make an issue of pronunciation to your face. If they do, either ignore them, or if you are feeling brave, fight back (verbally!) and engage in a bit of banter, you may even make a friend or two!