A dogpile is a social media phenomenon in which a large number of comments criticize something in a disorderly way, long past any necessity for making the point and generally without regard to any ameliorating factors.
While this can happen as criticism of a given post (as in the Urban Dictionary's definition), in which case the damage is usually confined to the group involved, it is also used as a tactic for online bullying and harassment: a post holds up a non-privileged individual or group for ridicule, and others "pile on" in the comments without any consideration for whether the ridicule is deserved or even accurate. Commenters and onlookers may even be encouraged to take other action against the individual (inductive terrorism). This technique is fundamentally right wing in nature, even if the participants appear to be left-oriented, in that it "punches down" rather than "punching up".
Wikipedia: as of 2020-09-05, article is about an eponymous search engine RationalWiki: as of 2020-09-05, has several mentions but no page Social Justice Wiki: no mentions as of 2020-09-05
- Urban Dictionary