Meghan Markle and Prince Harry marked their first public engagement together on Thursday with a visit to New York City's One World Observatory at the World Trade Center. There, the mum-of-two was addressed differently by one of the reporters.

Journalist Kyle Mazza was on the site when he asked the former "Suits" star how she feels about being back in the city. While the couple posed for photos, he called her Madam Duchess and asked "are you enjoying your time in New York?"

The 40-year old replied, "It's wonderful to be back, thank you." Prince Harry reacted to his wife being called Madam Duchess as he was seen on video smiling at her as he repeated the words.

"Prince Harry & Madam Duchess of Sussex Meghan Markle tell me on 9/23/21 that it feels wonderful to be back in NYC. Mayor de Blasio expresses his admiration saying they are wonderful guests and that the work they are doing is so important for our whole country and our whole world," Mazza wrote on Twitter along with a video of his interview.

It seemed "Madam Duchess" is a big hit with fans with some calling it an "awesome" nickname and liking how it sounds. One wrote, "Madame Duchess is an AWESOME coined term- and it's going to be monumental. You found a way to address her that's American, professional, and accomplished, and doesn't need British rules and say-so. Go you!"

Another chimed in, "You are the first one to call a royal "Madam Duchess" Kyle...and I love it. Cheers to that."

One fan suggested, "Trademark Madam Duchess because it's about to take off!" and one more reacted, "It made me smile so much... thank you for brightening our mornings with the important questions."

Mazza explained why he called Meghan Markle "Madam Duchess" as opposed to just using her royal title of Duchess of Sussex. He said it was to show her respect as he always wants to respect everyone.

"Dignity, respect, and communication is so important. I appreciate and thank Prince Harry and the Madam Duchess of Sussex for taking the time to answer," he said.

Prince Harry and Meghan Markle are in New York City for their first public engagement since they welcomed Lilibet Diana on June 4. They went on parental leave after her birth.

Prince Harry and Meghan Markle
Th Duke and Duchess of Sussex Photo: AFP / Daniel LEAL-OLIVAS