Megathread
A single official thread where all discussion about a major event is channeled, to prevent the forum/subreddit from being flooded with hundreds of duplicate posts. The community's way of handling a news storm.
Mechanic: during a big event (product launch, sports match, disaster, season premiere) the moderators create a pinned megathread and remove separate posts about the same thing with a pointer to it. Win: it keeps everything in one place (easier to follow), avoids the front page being drowned in duplicates, and gathers the collective reaction in real time. Common as a "Live Thread" or "Daily Discussion". Trade-off: it can feel stifling (everything is crammed together) and fast-moving (comments rush by). A central moderation technique in large communities, related to Bluesky/Twitter's lack of the same structure. Related to subreddit wiki and pin message.