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.

See also: Thunderbolt

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.