picking parts of a different culture that sound cool to you and use it for your own benefit, to give you some cultural cache. You still think the people who produced this culture are not on par with you. Whites don't think native americans are on par with them so using apache for name is cultural appropriation.

corollary, picking up something from white culture like wearing jeans isn't appropriation because whites have established themselves as top dog already.

Its pretty simple, really.