Question on terminology

The west, the global north, developed countries, the imperial core. I understand and am aware of some of the etymological differences between these words, but what is their difference in practical terms?

It seems that from a Marxist perspective these are one and the same, all designate the same grouping. I hear the west the most often in Lemmygrad, but which term is the most precise, or which might be the best to use?

I'd like to hear your perspectives and analysis.