When my Morris team toured in England, we discovered that it's the words that mean different things in the two countries that get you in trouble ...
The team's regalia includes black knee-britches. In the U.S., the term for knee-britches is knickers (shortened from Knickerbockers sometime in the first half of the twentieth century.) When a team member referred to his knickers, he discovered that the word means something different in Britain.
A similar thing happened to a college friend of mine who went to teach in Australia. The rubber-soled shoes that are called plimsoles in Britain and Australia are called sneakers in the U.S., and her students were only allowed to wear them in gym class. When she saw them come back from gym still wearing their rubber-soled shoes, she told them to take off their sneakers, all they did was stare at her and giggle. The only way they could make sense out of "take off your sneakers" was to interpret it as an instruction to take off their knickers, which they weren't about to do!