"Third World" referred to countries that remained non-aligned with either NATO or a grouping of states aligned with who?
Third World According to "Online Etymology Dictionary" the term Third World was formulated in 1952 by French economic historian Alfred Sauvy to mean countries that were neither part of the West nor of the Iron Curtain. Thus the term originally had a political meaning as it arose during the Cold War to define countries that remained non-aligned with either NATO or the Communist Bloc. The United States, Canada, Japan, South Korea, Western European nations and their allies represented the First World, while the Soviet Union, China, Cuba and their allies represented the Second World. This terminology provided a way of broadly categorizing the nations of the Earth into three groups based on political and politically-related economic divisions.
Three-world model The terms "First World", "Second World", and "Third World" were originally used to divide the world's nations into three categories. The model did not emerge to its end state all at once. The complete overthrow of the pre–World War II status quo, known as the Cold War, left two superpowers (the United States and the Soviet Union) vying for ultimate global supremacy. They created two camps, known as blocs. These blocs formed the basis of the concepts of the First and Second Worlds.