Related Clues:

• Grenade ingredient
• Trial balloon, e.g.
• One with steady nerves, slangily
• Blow-up cause?
• ''Hey, what's the big ___?''
• Gray matter creation
• Patent basis
• Tongs user
• Old supplier
• Content of cognition
• Blast creator
• ''What's the bright ___?''
• Asset for an entrepreneur
• Result of cogitating, perhaps
• Piece of mind?