"I am concerned, therefor I am right." The assertion that if one is coming from a position of concern (for the feelings of others, or a specific problem), then their conclusions must be viewed as credible.

The polite way to say "fuck off" to someone who has shown concern about a problem you're having when you don't want them in your business. Often used when you just wanted to rant about how horrible your life is rather than do anything about it, or when you hadn't intended for the news of your problem to reach this person. Almost always followed by an explanation of how you have everything under control now.

When you say that you care about something, but actually do not care. Unlike sarcasm, then intention is for others to think that you really do care.

A concerned citizen is a citizen of a country, often uneducated or stupid, that is concerned by a subject recently brought to his attention, most of the time by the media but can also be from other, more local sources, like a neighbor, even if the subject never affected his life in any way prior to the hearing of it.

A sleazy way to discredit anyone who disagrees with your point of view, especially if that point of view can cause physical harm to others.

A concerned citizen is a citizen of a country that is extremely concerned about a subject he just saw on TV, even if said subject does not affect his life in the slightest. Sometimes, the concern becomes permanent. When that happens, it is considered a mental illness.

1. (Noun) The Concern Troll differentiates itself from more outwardly nasty cousins by using generally polite language and claiming to agree with their victims. They then claim that their victims are essentially "doing it wrong," to help, they offer advice which would either invalidate their victims' position, cause an inherent hypocrisy with their philosophy, or render them unable to effectively advocate for it.

Their first known appearance was in talk radio, where they would open up their call with, "I'm such a huge fan, and you're always right, but..." usually followed with statements completely at odds with the philosophy governing the show. They were nicknamed by some as "seminar callers," because progressive groups in the USA had actually funded seminars where they taught followers to use this tactic against opposition voices on the radio in the '90s. These deceptive practices and individuals have since metastasized into the internet.

This is why most Concern Trolls are found on boards or the comment sections of political subjects; they use this tactic to attempt to sow seeds of doubt, and weaken their political opposition. Most are left-wing progressives, although a smattering of alt-right Concern trolls have begun to appear.

The cure for the typical nasty troll is the simple statement, "don't feed the trolls," i.e., ignore them. The cure for the Concern Troll is, "NEVER TAKE THE ADVICE!" (And if you are attracting them, likely you are doing something right)