Merriam-Webster Collegiate Dictionary - vietnam

 geographical name country SE Asia in Indochina; state, including Tonkin & N Annam, set up 1945-46; with S Annam & Cochin China, an associated state of French Union 1950-54; after civil war, divided 1954-75 at 17th parallel into republics of North ~ (capital Hanoi) & South ~ (capital Saigon); reunited 1975 capital Hanoi area 127,207 square miles (330,738 square kilometers), population 70,454,000