Cochin China, also known as Nam Ky in Vietnamese, was a historical region located in southern Vietnam. Synonyms for Cochin China include Saigon-Gia Dinh, Southern Vietnam, and Mekong Delta. Saigon-Gia Dinh referred specifically to the city and surrounding areas, while Southern Vietnam encompasses a broader geographic area that includes the Central Highlands and coastal areas. The Mekong Delta, on the other hand, refers to the region where the Mekong River flows into the South China Sea, including parts of Vietnam, Cambodia, and Laos. Each of these synonyms provides a unique perspective on the region's history, culture, and geography, highlighting its diversity and complexity.