"You canker blossom!" 3 Shakespearean Insults
Derogatory name for the extreme radical members of a group, especially in politics: “The candidate referred to the organization as being on the lunatic fringe of conservatism.” The term was coined by Theodore Roosevelt.
The radical and irresponsible sector of a group or party: The party has been turned over to its lunatic fringe
[1913+; apparently coined by Theodore Roosevelt in History as Literature]