Third world country

What do you understand by that?  I imagine you take it to mean a poor, under-developed country. And yet, that's not how it started out.  The phrase originated in the Cold War era, when the United States and Western Europe was considered the First World, the Soviet Union and associated countries the Second World, and any country not affiliated to either of them, a third world country.  So in the beginning it was a political rather than a social designation.