Unlike "the Silk Road" or "the Middle Ages", "third world" was a term in contemporary use at the time it applies to, including among non-aligned states and NGOs that worked on third world cooperation.
It was pretty well-defined as political classifications go, and people involved in actual "entities" related to it were aware of and sometimes used the term.
It was pretty well-defined as political classifications go, and people involved in actual "entities" related to it were aware of and sometimes used the term.