Giao Chỉ

Jiaozhi (Chinese: , ; pinyin: Jiāozhǐ; Vietnamese: Giao Chỉ, Tai: kɛɛu^A1, Wade-Giles: Chiāo-chǐh), was the name for various provinces, commanderies, prefectures, and counties in northern Vietnam from the era of the Hùng kings to the middle of the Third Chinese domination of Vietnam (c. 7th–10th centuries) and again during the Fourth Chinese domination (1407–1427).

The name of the territory was also used to refer to the Lac people and their ancient language. It seems to be a Yue or Viet endonym of uncertain meaning, although it has had various folk etymologies over the years. In his Tongdian, Du You wrote that "The Jiaozhi are the southern people: the big toe points to the outside of the foot, so if the man stands up straight, the two big toes point to each other, so people call them the "jiaozhi"." (The Chinese character means "hallux, big toe".) The Ciyuan disputed this:

The meaning of the word Jiaozhi cannot be understood literally, but the ancient Greek method of "opposite pillar" and "connecting pillar" to label humans on earth—where "opposite pillar" stood for the South side and its logical opposite the North side, whilst "connecting pillar" stood for the East side with the West side connected to it—could provide a suggested origin. If Jiaozhi was intended to characterize "opposite pillar" because this was what people of the North called the people of the South, then the feet of the North side (chân phía Bắc') and feet of the South side (chân phía Nam) must oppose each other, therefore rendering it impossible for the feet of a person to cross or intersect each other (không phải thực là chân người "giao" nhau).

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