"High teen" is a Konglish (a mishmash of Korean and English) term that comes from "high school" and "teenager", and refers to various aspects of pop culture as it relates to young people.
Today, it is more commonly used to refer to Western coming-of-age movies and television dramas like Clueless and Gossip Girl.
In fashion, high teen translates into preppy pieces such as pleated skirts and tartan patterns.
Looks and items from the 1990s or early 2000s, such as the outfits worn by Cher Horowitz in Clueless or baguette-style handbags and scrunchies, are fast becoming a staple in every youth's wardrobe in South Korea, as are candy-coloured crop tops and wide-legged jeans.
A quick scan of clothing websites popular among teens attests to that, with items such as cardigan sets and sheer, off-the-shoulder ribbed tops high on the bestseller pages.
Although the trend has cemented itself as a mainstay in South Korea this year, it was first popularised last year by Jennie Kim of K-pop girl group Blackpink, who is considered something of a fashion icon in the country.
Many have praised her "high teen" looks that come from her fashion style, overseas upbringing and natural charisma.
In 2017, during Blackpink's As if it's Your Last single promotion tour, the group's members wore preppy outfits with a punk edge, such as school-uniform-inspired looks worn with crop tops, chain belts and knee high socks.https://twitter.com/BLACKPINK_PH/status/880161684135882752
Whatever Jennie wore, like a vintage Chanel crop top and cargo trousers, mainstream shopping sites started to mass-produce.
In 2019, music fans and fashion lovers noticed she started wearing statement pieces from the early 2000s, like pointelle knit crop tops and wide-legged jeans, as well as sporting short-handled shoulder handbags and wearing silk scrunchies. As a result, shops around Seoul started stocking imitations of what she was photographed in.
Jennie's style is often picked apart and analysed by fashion bloggers and YouTubers such as JewCookMe, who covers the fashion styles of many K-pop stars. Her videos typically average 100,000 views but the ones that focus on the 24-year-old Jennie often have more than a million hits.
In an interview with Elle Korea, Jennie has stated she is "interested in things that aren't from her time and age, be it fashion or other things".
Many YouTubers are on the same page as her, and upload videos on how to dress "high teen" with outfits and styles from before their time.
Freezia, a popular Korean fashion and beauty model turned YouTuber, shows off her take on the look in a video titled "I Tried Dressing Like a High Teen Movie Female Lead", featuring matching cardigan and halter top sets with flouncy skirts and calf-length socks. It's a look that is especially popular among students in South Korea.
Fellow influencer Stephany Haery Kim has a large following on TikTok and Instagram thanks to her high teen looks, and her popularity has led her to set up Raichee Kitsch - a photo and prop studio which provides a space for those who enjoy the retro aesthetic to shoot their own looks.
High teen doesn't just cover bags and clothes, though - the term can refer to make-up and hairstyles, too. A recent hairstyle that has come back into fashion uses bobby pins or coloured clips to pin back hair from both sides of the face.
Another style employs the use of a claw clip. In make-up, more people are experimenting with pastel eyeshadow, and frosted or glossy lips.
The high teen trend is seen as part of a retro wave in South Korea. There, cultural experts term it "newtro" - a fusion of the new and the retro. Flip phones - like Samsung's Z Flip - are making a comeback.
Coming full circle from Jennie, the trend's popularity is bleeding back into K-pop with Oh My Girl's recent comeback album art featuring bright, "newtro" pop art.
Music videos now nod back to the heartthrobs of the early 2000s, like in trending boy group NCT 127's music video for Dreams Come True, which uses heavy backlighting and a white backdrop that is very reminiscent of how US boy band NSync used to film theirs.
This article was first published in South China Morning Post.