an especially luminous meteor (sometimes exploding)
source: WordNet 3.0
a highly energetic and indefatigable person
source: WordNet 3.0
a ball of fire (such as the sun or a ball-shaped discharge of lightning)
source: WordNet 3.0
the luminous center of a nuclear explosion
source: WordNet 3.0
A ball filled with powder or other combustibles, intended to be thrown among enemies, and to injure by explosion; also, to set fire to their works and light them up, so that movements may be seen.