noun
Second World
Cold War term for the Soviet Union and its allied communist states, contrasted with the First World (Western bloc) and Third World (non-aligned nations). Now largely historical.
冷戦時代、ソ連や東欧諸国は第二世界と呼ばれた。
During the Cold War, the Soviet Union and Eastern European countries were called the Second World.
Compound of 第二 (second) + 世界 (world), calque of English 'Second World', a Cold War geopolitical classification.