If you want to join the ranks of the British royal family, there are certain things you just shouldn’t say. Mentioning the rancorous divorce of Prince Charles and Princess Diana or speculating how much longer Queen Elizabeth II will remain alive and keep Charles waiting to be king might be obvious. But there are some unexpected words that are also, if not banned, then certainly frowned upon in Buckingham Palace.

In an interview with Hello! magazine, social anthropologist Kate Fox, author of “Watching English: The Hidden Rules of English Behaviour,” has identified eight words others might throw about unthinkingly that are no-nos among the ultimate British elite. It is a list that currently has special relevance with Kate Middleton on the lookout for a new personal assistant and increased speculation about American actress Meghan Markle marrying Prince Harry.

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According to Fox, while both Markle and the Duchess of Cambridge’s new assistant might think they will sound terribly polite by saying “pardon,” the correct response in royal circles when mishearing someone is “sorry or what.”

The word “posh,” something which the royal family could most certainly be described as is also off-limits. Instead, the royals prefer “smart.” Perhaps less surprisingly, rather than spraying yourself with “perfume,” Markle will have to get used to spritzing herself with her favorite “scent.” And instead of describing an evening meal as “tea,” as is habitual in many parts of England, “dinner” or “supper” is preferred.

There are yet bigger vocabulary challenges for royal newcomers. Among the 775 rooms in Buckingham Palace, not one is called a “lounge.” Rather, the queen and her family gather together to relax in a “sitting room” or “drawing room.

But most intriguingly of all, the royals never use a “toilet,” instead doing their less than royal business on a “lavatory” or “loo.” The reason, according to Fox: because of the French origins of “toilet.”