Prince William reportedly calls Kate Middleton “poppet.” But the unique term of endearment apparently has a controlling connotation.

Psychologist Dr. Becky Spelman recently told The Sun that “poppet” has various meanings depending on who’s using the term. In Middle English, the word could either mean a small child or a poppet, which is used to practice witchcraft.

But in modern English, the term is used to refer to a woman in a sweet manner. “Poppet” is also used to refer to “dear” or “sweetie,” Spelman said that the Duke of Cambridge must have chosen the moniker to refer to his wife to show his affection and desire to protect the Duchess of Cambridge.

However, the term “poppet” also has a negative connotation. It suggests that Prince William is somehow controlling Middleton and supervising her every move.

“Prince William’s use of the word for his wife is affectionate and reflects his admiration for her beauty and his desire to protect and care for her—and perhaps, to some extent, also to control or at least supervise her movements so that he feels that he is at the helm of their relationship,” she said.

Spelman went on to explain why Prince William might feel the need to supervise his wife. She said that this may come from his inherent awareness that as members of the royal family, they are always in the public eye.

Meanwhile, Prince William is not the only member of the royal family who has a nickname for his wife. Prince Philip reportedly calls Queen Elizabeth II cabbage. Royal biographer Robert Lacey previously told The Sun that the term is used as an abbreviation for the French term “mon petit chou.”

When Princess Diana was still alive, she used to call Prince William “wombat.” During a previous interview, the Duke of Cambridge said that his mom came up with moniker while they were in Australia but it’s not because he looks like a wombat.

Kate Middleton and Prince William
Prince William and Kate Middleton attend the 1st Battalion Irish Guards St Patrick's Day Parade at Cavalry Barracks on March 17, 2019 in Hounslow, England. Getty Images/Gareth Fuller