Related Clues:

• Tourney ranking
• Inventor's ''step one''
• Bright one from gray matter
• Rank at Wimbledon
• Inventor's start
• Seed
• Light bulb's signification, in cartoons
• Light bulb, in comics
• Mental glimmer
• Object of thought
• Head piece?
• Creator's sine qua non
• Brainchild
• Number one at Wimbledon, e.g.
• Theory