Sea-lioning is the act of jumping into discourse communities you are not a part of with demands for evidence. Sea-lioning usually maintains a pretense of civility, but ignores incessant requests to desist. The term comes from a well-known Wondermark comic strip where a sea lion overhears a passing remark about sea lions and persistently demands support for the comment. (html)
It’s important to note that while many see sea-lioning as bad behavior, it is behavior that is produced in part by Inhospitable Writing.
Sea-lioning is related to Concern Trolling, a malicious form of discourse meant to divide communities by posing as a “concerned member” of those communities. See Concern Trolling