A message board posting technique designed to end or derail threads that its user finds uninteresting or lacking productive discussion. This technique involves posting screencaps from the 1967 Spider-Man cartoon series with humorous captions unrelated to the original thread topic. The user generally initiates a Spiderman thread with captions intended to declare that the original thread topic will no longer be discussed. Occasionally, additional users contribute to the derailing with their own screencaps of Spider-Man. Frequently used on 4chan's various message boards, where the technique originated. Generally used to derail threads about incest or "wincest."

A buzz word being used to refer to creators and influencers forming or encouraging unhealthy relationships with their fans. Usually used in the context of young audiences feeling they have a relationship with the influencer due to the huge amount of the influencer’s content they consume. The influencer in question, however, is unaware of the fan’s existence other than the general knowledge of having fans. Common examples include Dream and his stans. These relationships are exacerbated by the influencers confirming they have more than a creator-to-viewer relationship.

The word is circulating due to various YouTube essays about the phenomenon using the word, and therefore people who enjoy complaining about influencers repeating what they heard in the video in any comments section they can find.

Spiderman threads are pretty much the best thing ever. The definition is self-explanatory.