People in both the United States and the United Kingdom generally speak English, but there are plenty of words whose definitions have changed on one side of the pond or the other. If you are going to communicate with someone who speaks a different dialect than what you are used to, it would help to know which words may be confusing. Here are a few examples.
3. Pants
It’s fine for a man to wander outside in America wearing nothing but pants. In Britain? Not so much. In the U.S., pants go on top of underpants or underwear, which are called pants in the UK. Brits wear trousers over pants.
4. Jumper
If you’re an American who read the British version of the Harry Potter series, you probably wondered why all the boys so often wore jumpers. In the UK, a jumper is a sweater, not a sleeveless dress that goes over a blouse (that’s a pinafore).
The list at Mental Floss covers more than just clothing, but it doesn't explain why a man named Randy should go by Randall when visiting Britain, nor exactly which body part a fanny is. But it will tell you something you probably don't already know.