n. 1. A shaft of lightning; a brilliant stream of electricity passing from one part of the heavens to another, or from the clouds to the earth. [ 1913 Webster ]
2. Something resembling lightning in suddenness and effectiveness. [ 1913 Webster ]
The Scipios' worth, those thunderbolts of war. Dryden. [ 1913 Webster ]
3. Vehement threatening or censure; especially, ecclesiastical denunciation; fulmination. [ 1913 Webster ]
He severely threatens such with the thunderbolt of excommunication. Hakewill. [ 1913 Webster ]
4. (Paleon.) A belemnite, or thunderstone. [ 1913 Webster ]
Thunderbolt beetle (Zool.), a long-horned beetle (Arhopalus fulminans) whose larva bores in the trunk of oak and chestnut trees. It is brownish and bluish-black, with W-shaped whitish or silvery markings on the elytra. [ 1913 Webster ]