'Fireball' definitions:

Definition of 'fireball'

From: WordNet
noun
An especially luminous meteor (sometimes exploding) [syn: bolide, fireball]
noun
A highly energetic and indefatigable person [syn: powerhouse, human dynamo, ball of fire, fireball]
noun
A ball of fire (such as the sun or a ball-shaped discharge of lightning)
noun
The luminous center of a nuclear explosion

Definition of 'Fireball'

From: GCIDE
  • Fireball \Fire"ball`\, n.
  • 1. (Mil.) 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. [1913 Webster]
  • 2. A rare phenomenon often associated with or caused by lightning, resembling a luminous ball of fire passing rapidly through the air or along solid objects, then disappearing, and sometimes exploding. It seldom lasts more than a few seconds. Also called ball lightning, globe lightning, globular lightning, or kugelblitz. [Webster 1913 Suppl. +PJC]
  • 3. A large mass of fire caused by a large explosion, as of inflammable liquids or a nuclear device. The larger fireballs, as of nuclear explosions, rise seemingly intact into the air and may reach high altitudes while still glowing. [PJC]

Synonyms of 'fireball'

From: Moby Thesaurus