Answer: PRISM
The answer PRISM has 160 possible clues. See the results below.
Possible Clues:
- Device in Newton's refraction experiment
- Po-faced about school sending colourful types in a number of directions
- Rainbow projector
- Beam-splitting object
- Spectrum-showing crystal
- Prime Minister stopped by retired teacher in shape
- Light separator
- Son cutting proper glass object
- Crystal that splits light
- Spectrum-showing glass