She's perfected the royal curtsy, and now Meghan Markle has taken on the "duchess slant"

She’s perfected the royal curtsy, and now Meghan Markle has taken on the “duchess slant.”

During her official debut alongside Prince Harry, Prince William and Kate Middleton on Wednesday, Meghan was twinning with her future sister-in-law on stage as the foursome highlighted The Royal Foundation.

The duo were both implementing the “duchess slant,” a distinctive move, in which the knees and ankles are clasped firmly tighter and the legs are slanted to the side, creating a flattering silhouette.

Meghan Markle and Kate Middleton
| Credit: Chris Jackson - WPA Pool/Getty

The unofficial term, first coined by Beaumont Etiquette, is named after the Duchess of Cambridge and her now go-to pose. (Her late mother-in-law, Princess Diana, was also a fan of the pose.)

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It’s a pose Kate has struck many times before — most notably when she posed alongside Prince William at the Taj Mahal in 2016 in a photo that was very reminiscent of Diana’s iconic shot in 1992.

Princess Diana Kate MiddletonTim Graham/Getty; Zak Hussein/Getty
Credit: Tim Graham/Getty; Zak Hussein/Getty

“Typically the ‘duchess slant’ is used when a lady has to sit for an extended amount of time while keeping poise and posture,” Myka Meier, royal etiquette expert and founder and director of Beaumont Etiquette, tells PEOPLE. “It is the perfect pose for when a camera is shooting directly in front of you because by slightly slanting the knees to create a zig-zag effect when wearing a dress or skirt, your legs are angled so that the camera only shoots the sides of your legs and protects your modesty.”

Meier also adds that the slant helps make your legs look longer when sitting.

“‘The Duchess Slant’ is one of the most elegant and flattering ways to sit, because it has a lengthening effect on the legs,” she says. “The key with the technique is to square your shoulders straight ahead while maintaining perfect posture. Keeping knees and ankles together at all times, position your legs so that you create a slant, angling your knees to the side. Hands should be folded one over the other and placed in your lap.”

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Kate Middleton
| Credit: Peter Nicholls-WPA Pool/Getty Images

As Meier, notes, one of the “biggest etiquette mistakes a lady can make” is to cross her legs at the knee. Instead, women should sit with their knees and ankles together and should only cross their legs at the ankle if needed. “It’s sophisticated, protects vulnerabilities and looks fabulous in photos,” Meier says.

Turns out, when you’re a royal, even the way you sit is carefully orchestrated around etiquette.

  • With reporting by MARIA MERCEDES LARA