re: Really------well actually........
the term most used has been dependencia, and was coined by Andre Gundar Frank for the UN. Obiously the orignial reference was for Latin American countries, but by extension has been applied wherever deemed applicable.
Interestingly, the only time this description wasn't used to describe a US/South American relationship was to explain the relationship between Colombia and Peru--in which Peru was dependent for the larger part of its foreign currency on selling cocoa leaves to Colombia. In neither case did the IMF describe the activities as imperialism.