Yes, but the "never to be heard from again" may be wishful thinking. Trolls sometimes hang around and continue to poke and prod. Not saying you're a troll, just addressing the question.
So a troll is a newbie with an opinion different from those of others? Or an inquisitive person who asks a lot of questions no one wants to hear?
Ugh. No matter.
No, go back to your original definition, add "intentionally" and that's what at troll is. Sometimes it's a guessing game about the intentionality, other times obvious.