九真

Etymology
and propose that  transcribed *k.cin, a local autonym which is reflected in 🇨🇬 & 🇨🇬 meaning "human being, people", the latter from 🇨🇬, which consists of prefix *k- and ; thus, "human beings" are "(those who are) on foot, those who stand on their feet."

Pain further suggests that " might therefore have been inhabited by some ancestors of the Southern Vietic Thavung - Aheu."