The word 东北 (dōngběi) is a compound noun formed through the method of coordinate combination, where two characters with related meanings are joined to create a new, specific concept. It literally combines 东 (dōng, "east") and 北 (běi, "north") to mean "northeast", functioning grammatically as a place word. While it can denote the cardinal direction, its primary lexicalized meaning is as a proper noun referring to China's Northeast Region (historically Manchuria), encompassing the provinces of Liaoning, Jilin, and Heilongjiang. Thus, its formation is a direct semantic fusion of two directional radicals to designate both an orientation and a definitive geographic entity.