former southernmost province of the Chinese Empire, now northern Vietnam
Definitions (Wiktionary)
name
(historical) Jiaozhi (the ancient Chinese commandery in northern Vietnam first established under the Han dynasty)
name, historical
Jiaozhi (a generic term for the lands south of the Five Ridges (Dayu, Qitian, Dupang, Mengzhu, and Yuecheng) in Liangguang, essentially comprising North Vietnam)