1. (n.) One who upholds secession.

2. (n.) One who holds to the belief that a State has the right to separate from the Union at its will.

abjuratory apostate backslider bolter breakaway collaborationist collaborator convert defector deserter fifth columnist mugwump mugwumpian mugwumpish proselyte quisling recidivist recreant renegade renegado renegate renunciative renunciatory repudiative repudiatory reversionist revocatory runagate schismatic seceder separatist strikebreaker tergiversant tergiversator traitor turnabout turncoat turntail