How do you define it?
As far as the world is concerned, China means People's Republic of China.
Taiwan is not part of that.
China is a political term, not geographic.
You ask me how I define "China"? I define it in much larger and broader terms than just the PRC.
"China" has been around for 5,000 years. The PRC has been around for 50 years. You can do the math...
As far as it not being a geographic term, who knows...
Right now, the political definition of "China" is still up in the air. What about the ROC? Or the PRC? Couldn't there conceivably be a new way to define that word?
If you ask me to be specific in what I believe (other than what I said above), I cannot do it without a lot of thought.
"China" is an English term, not a Chinese one.
The "middle kingdom" refered to the kingdom of the monarch, however big or small that kingdom might have been...
Translate that the English and what do you get?
Geographically "China" has changed sizes more times than I can count. There have historically been many "China's".