I don't think a formal definition of the word "troll" would be useful; the term is used somewhat informally to the general blob of "problematic users" - trolls, idiots, cranks, aggressive and self-centered users, people who won't shut up about their pet topic, etc. - the borders are somewhat fuzzy, and any attempt to try to formalize them is likely to be too broad or too narrow. Would you be able to properly formalize the kind of behavior you don't want on a website you run, without being too broad or too narrow? "Troll" is a bit like an unambiguous example of the class of behaviors to be discouraged, but if the policies hit a broader target and also discourage non-trolling obnoxious cranks and idiots, that's a feature, not a bug. Incidentally, I agree that using 'trolling" to describe any downvoted comments (like the "troll toll") is somewhat unfortunate, meany downvoted comments are from users who sincerely want to convince everybody that if they would stop being blinded by politically correct groupthink they would recognize that lizard-men are controlling the government. But then, "troll toll" has a nice ring to it.