> "one persons terrorist is another persons freedom fighter"

yes, but only to weak-minded cultural relativists.

I don't mind stating a definition explicitly. If you would consider killing nonviolent civilians, merely to send a message to others or to prove yourself to your "god," you're a terrorist.

Note: The only real complexity in the definition is that during war, embedding military equipment among civilians happens sometimes, and when it does, it's the ones choosing to do that, war criminals by definition, who bear the responsibility for those innocent deaths when those locations then become legitimate military targets.

I'll omit giving examples to avoid triggering those who like to "bothsides" some of the more well-known terrorist groups lately.