A beetle (Lytta, or Cantharis, vesicatoria), havin1g an elongated cylindrical body of a brilliant green color, and a nauseous odor; the blister fly or blister beetle, of the apothecary; -- also called Spanish fly. Many other species of Lytta, used for the same purpose, take the same name. See Blister beetle, under Blister. The plural form in usually applied to the dried insects used in medicine.
- A brilliant green blister beetle (Lytta vesicatoria or Cantharis vesicatoria) of central and southern Europe.
- A toxic preparation of the crushed, dried bodies of this beetle, formerly used as a counter-irritant for skin blisters and as an aphrodisiac.