Enter a clue or pattern or both:
The Clue
Gunpowder ingredient (9 letter answer)
The Answer
SALTPETER
Tags
Notes
The answer SALTPETER is so rare that it appears less than once every 2500 puzzles.
Definition
SALTPETER as a noun:
1. (potassium nitrate, saltpeter, saltpetre, niter, nitre) = (KNO3) used especially as a fertilizer and explosive