Based on that definition, a conservative is someone who wants to preserve the existing order, whatever it might be at any point in time at any place in the world.
The root of the words conservatism and conservative is conserve, in other words to preserve. In any society or human endeavor, conservatives are traditionalists who resist change. That's the meaning of the term.
If I understand your above sentence correctly, where you go wrong is in your second clause. It isn't correct to say that conservatives want to preserve the existing order any place in the world at any time. It is correct to say that conservatives want to preserve the traditions of their own cultures and societies.
In the United States, when used as a political term, a conservative wants to preserve the Constitution, our system of government, our sovereignty, what are thought to be traditional American values (some people express it as Judeo-Christian values), human life, and so on.