Related Clues:
- New thought
- Reason to shout "Eureka!"
- "Hey, what's the big ___?"
- Invention inspiration
- Flash in the brainpan
- Certain germ
- Mental invention
- Bright thing?
- "Whose bright ___ was this?"
- Crossword constructor's germ
- Innovator's inspiration
- Invention starter
- Mental germ
- Basis of an invention
- Invention genesis