Even with the spike in usage of Britishisms, there are still a number of words and phrases that can baffle even the most pretentious BBC America fans. Next time you’re in London, keep these translations to hand—or as the Yanks would say, nearby—and you’ll be just fine.
1. Knock up: To wake up. Don’t freak out if your flatmate says he will be sure to knock you up in the morning.
2. Pants: Underwear. Be careful not to compliment your friend’s new pants, or she will be very confused. Trousers or slacks are what you wear over your pants.
3. Take the piss: To take advantage of; to ridicule. This is one of the more unattractive British phrases that show up frequently in conversation.