Whats the definition of abusing economy?

Q u o t e:
ive hear players getting banned for this. and im worried because i've made a lot of gold from auction house by buying cheap mats, craft and sell. can i be banned for that?

As long as what goes through the AH is achieved by legitimate means, it's a free-market system, Cg.

Exploitation of economy usually deals with trafficking in illicit virtual goods or funds, or some involvement therein.