Everybody knows that history , terms change with time, as someone who has lived all his life in the 3rd world, I have never met even 1 person who is offended by the term (I have met online a lot of first-worlders offended though). We use the term as sarcastic self-mockery and as encompassing umbrella to identify ourselves with nations all over the world under the same predicaments. Proud tercermundista here.