Related Clues:

• Member of the other side
• Start to knock?
• Role played by everyone, it's said
• Freeze front
• Matter or body start
• Start to freeze
• ___-inflammatory
• Dissenting one
• Dead set against
• Opposition member
• Climactic beginning?
• Like some debaters
• Not a pro
• Picketer, perhaps
• Prefix with proton or ballistic