- any large fire in brush, forests, or open spaces that spreads rapidly and is hard to extinguish.
- a highly flammable composition, such as Greek fire, difficult to extinguish when ignited, formerly used in warfare.
- sheet lightning, unaccompanied by thunder.
- the ignis fatuus or a similar light.
- a disease of tobacco and soybeans, characterized by brown, necrotic spots, each surrounded by a yellow band, on the leaves and caused by the bacterium Pseudomonas tabaci.
- erysipelas or some similar disease.
- a highly flammable material, such as Greek fire, formerly used in warfare
- a raging and uncontrollable fire
- anything that is disseminated quickly (esp in the phrase spread like wildfire)
- lightning without audible thunder
- another name for will-o'-the-wisp
