Wildfire
Wildfire , noun
1.
A composition of inflammable materials, which, kindled, is very hard to quench; Greek fire.
Brimstone, pitch, wildfire... burn cruelly, and hard to quench.
2.
(a) (Medicine) An old name for erysipelas.
(b)
(Medicine) A disease of sheep, attended with inflammation of the skin.
3.
A sort of lightning unaccompanied by thunder. [Rare]