Tourism is when you go to a destination inboundly or outboundly?

Answer 1

With no offense meant neither is a word, though you could have put quotation marks around them noting that you know that.

Tourism in a simple sense is travel, and especially to destinations frequented by others.

To be a tourist you merely have to go somewhere. You'll remain a tourist even as you return because you've BEEN somewhere.

Answer 2

You get many different classes of tourists.
The two main ones are Domestic tourists (IE tourists that stay in the country they are travelling in) and Foreign tourists (IE tourists that visit a country that they are not resident in.)

So both inbound and outbound travellers would be regarded as tourists

Answer 3

Yes.