Not science related, but the one that always throws me is hearing people from the rest of the world talking about football and having to remember it means the sport I think of as soccer rather than “American football.”

Maize vs. corn is definitely the most common conflict I hear between American and International English and there are a handful of others… though only “groundnuts” (aka peanuts) comes to mind… The proper name for pigs seems to be swine, but I don’t know if it’s for the same reason or not…