The Duchess of Sussex has left the city. After a five night stay to catch up with girlfriends and celebrate her royal baby in New York City, Meghan Markle headed back to the United Kingdom yesterday — but not before breaking a major royal style rule.

We break down the duchess’s off-duty look, ahead.

Meghan Markle’s airport outfit

On Wednesday, Meghan Markle was seen leaving New York City in an all-black athleisure getup, complete with a camel-colored coat for extra warmth, a large black tote bag, and a baseball hat.

According to InStyle, the duchess’s leggings were Lululemon leggings, an Ingrid & Isabel maternity zip-up, and Adidas UltraBoost sneakers. She also wore a new Jennifer Meyer nameplate necklace — presumably given to her by friends at her baby shower — featuring the word “mommy.”

She also borrowed a black baseball hat from her bestie and former co-star, Abigail Spencer (who wore the hat earlier in the trip) with “Rectify” embroidered on the front. Some royal fans thought it was a clue or message to Kate Middleton in the midst of their alleged royal feud. However, the hat appears to come from the television series, Rectify, which Spencer once starred in.

Royal family style rules

Albeit a chic take on athleisure, Meghan Markle’s airport outfit broke royal style rules. In the royal family, dressing casually — especially in athletic wear — is a big no-no, unless a royal engagement or event (such as the Invictus Games) calls for such attire.

That said, since the Duchess of Sussex was technically off-duty, the queen most likely didn’t mind her going out in public dressed in athleisure — especially since she still looked put together and as chic as ever.

Her airport look isn’t the only time Meghan Markle broke royal family style rules. Here are some of the ways she’s bent fashion protocol.

Ripped jeans

Depending on the royal engagement, jeans are allowed — so long as they fit within the “smart” style Queen Elizabeth prefers. However, when Meghan Markle and Prince Harry were dating, the now duchess accompanied her beau at the Invictus Games in a pair of ripped jeans by her favorite denim brand, Mother.

Messy hair

In the royal family, women must always wear their hair in a neat way. To ensure everything stays put, Kate Middleton has even sported a subtle hair net when wearing her locks in a low, pulled-back style. However, Meghan Markle has made the messy bun one of her signature looks.

Dark nail polish

The queen is extra uptight about nail polish. Her Majesty reportedly requests that the women in her family only wear nude nails, or opt for her personal favorite, a soft pink hue titled “Ballet Slippers” by Essie. However, Meghan Markle likes to switch up her style and painted her nails in a dark burgundy color for the British Fashion Awards.

Off-the-shoulder dresses

It’s fairly uncommon for a royal woman to bare her skin in the way Meghan Markle often does. The Duchess of Sussex has donned a few off-the-shoulder ensembles, which is also against royal family style rules.

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