There are two examples of "small waist" in historical materials: one is a small waist like a willow, which refers to a woman's slender waist. The second story is "The King of Chu has a thin waist". At that time, the geographical position of Chu State was regarded as a charming place by the Central Plains Dynasty, so the thin waist was not called "Chu waist" or "pretty waist".
The second theory seems more credible. But in history, the thin waist of King Chu (King Chu Ling) is not a woman's waist, but a scholar's waist and a man's waist. Once upon a time, King Chu Ling liked his courtiers to have slender waists. Therefore, the DPRK ministers only eat one meal a day to control their waistlines. Every day when they go to the front, they hold their breath and draw back their waist, and then tighten their belts, so that they can stand up against the wall. In the second year, the faces of civil servants in Manchu were black and yellow.
No matter in the Warring States Policy or All-Love, it is clearly written that "King Chu Ling is a good gentleman with a thin waist". During the Spring and Autumn Period and the Warring States Period, "scholar" was the proper name of the male group between Qing Dafu and ordinary people, and women were not qualified to be called scholars. So King Chu Ling likes a man's thin waist. Therefore, some experts speculate that King Chu Ling seems to be gay or bisexual. Otherwise, how can an open king of Chu have a hobby of loving a man's waist?
Later, we saw in many ancient books that "the king of Chu has a thin waist and there are many hungry people in the palace", which gradually evolved into a thin waist for women. This is an eternal misunderstanding.