Related Clues:

• Green prefix
• Environmental word form
• Former Prizm maker
• "Foucault's Pendulum" writer
• Friendly start?
• Budget, in brand names
• Prefix for system
• Earth-friendly lead-in
• Chevy auto
• Environment-friendly
• Semiotician Umberto
• Logical opening?
• Thermal start
• Italian novelist
• 'Green' prefix