Source: Lauren told me about this. Also: [1], [2], [3].
Sealioning is a type of trolling or harassment which consists of pursuing people with persistent requests for evidence or repeated questions, while maintaining a pretense of civility and sincerity. It may take the form of "incessant, bad-faith invitations to engage in debate".
The term originated with a 2014 strip of the webcomic Wondermark by David Malki, where a character expresses a dislike of sea lions and a sea lion intrudes to repeatedly ask the character to explain. "Sea lion" was quickly verbed, the term gained popularity as a way to describe online trolling, and it was used to describe some of the behavior of those participating in the Gamergate controversy.
