- (historical) A state, officially the Republic of Vietnam, that governed southern Vietnam in 1955-1975.
- 1971, Johnson, Lyndon, quoting John F. Kennedy, The Vantage Point, Holt, Reinhart & Winston, →ISBN, LCCN 74-102146, OCLC 1067880747, page 61:
- China is so large, looms so high just beyond the frontiers, that if South Vietnam went, it would not only give them an improved geographic position for the guerrilla assault on Malaya but would also give the impression that the wave of the future in Southeast Asia was China and the Communists. So I believe it.
former Asian country