- (Internet slang) Someone who posts to an internet forum or newsgroup, claiming to share its goals while deliberately working against those goals, typically, by claiming "concern" about group plans to engage in productive activity, urging members instead to attempt some activity that would damage the group's credibility, or alternatively to give up on group projects entirely.
- "The idea is to create dissent and discontent through misinformation but to have it accepted because you’re really not against whatever the general group there is for."
- "From the diaries. More cute concern trolls by Republican campaign workers -- kos"
- "Making Mischief on the Web, Time Magazine, Dec. 16, 2006 Definition of concern troll published in mainstream media.