It girl

"It Girl" was originally slang for a beautiful, stylish young woman who possessed sex appeal without flaunting her sexuality, when the phrase originated in British upper class society around the turn of the 20th century. An early literary usage of the term "it" in this context may be traced to a 1904 short story by Rudyard Kipling: "It isn't beauty, so to speak, nor good talk necessarily. It's just 'It'." The expression reached global attention in 1927, with the popularity of the Paramount Studios film It, starring Clara Bow. Elinor Glyn, the notorious English novelist who wrote the book It and the screenplay based on it, lectured: "With 'It,' you win all men if you are a woman and all women if you are a man. 'It' can be a quality of the mind as well as a physical attraction." Glyn, who first rose to fame as the author of the scandalous 1907 bestseller Three Weeks, is usually credited with the invention of the "It Girl" concept, although it predates her book and movie. But she is definitely responsible for the impact the term had on the culture of the 1920s.

The fashion component to the It Girl, however, originated with Glyn's elder sister, the celebrated couturier Lucy, Lady Duff-Gordon, known professionally as "Lucile," the name under which she directed exclusive salons in London, Paris and New York. As Lucile, Lucy Duff Gordon was the first designer to present her collections on a stage complete with the theatrical accoutrements of lights and music, inspiring the modern runway or catwalk show, and she was famous for making sexuality an aspect of fashion through her provocative lingerie and lingerie-inspired clothes. Lucile also specialised in dressing trendsetting stage and film performers, ranging from the stars of the Ziegfeld Follies on Broadway to silent screen icons like Mary Pickford and Irene Castle. As early as 1917 Lucile herself used the term "it" in relation to style in her fashion column for Harper's Bazaar: "... I saw a very ladylike and well-bred friend of mine in her newest Parisian frock ... she felt she was 'it' and perfectly happy."

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Wikipedia