Greater Yunnan is an ill-defined term which refers to Yunnan, China. In the fifteenth century, the region encompassed parts of Northern Southeast Asia and Northeast India. Some scholars use the term not to describe a geographical region centering mainly around Yunnan, but rather to describe China's modern influence over most of Southeast Asia.
See also
China Rim East and Southeast Asian relations with Northeast India Golden Triangle (Southeast Asia)
Further reading
Opposing hydropower development on China's Nu River: A disconnect between urban activists and local residents, provides background history of region within China
References