Related Clues:
- Invention genesis
- What a light bulb sometimes signifies
- Inventor's springboard
- "The very ---!"
- Sneaking suspicion, e.g.
- Starting point for an invention
- Head light bulb?
- Intangible spark
- 'If at first, the ___ is not absurd, then there is no hope for it': Einstein
- Something thought up
- Start of something big, usually
- It might be right or bright
- Something that can't be patented
- Inventor's inkling
- 'Drawing is putting a line round an ___': Henri Matisse