cantharis

(kănˈthər-ĭs)

1. A brilliant green blister beetle (Lytta vesicatoria or Cantharis vesicatoria) of central and southern Europe.
2. cantharides (used with a sing. or pl. verb) A toxic preparation of the crushed, dried bodies of this beetle, formerly used as a counter-irritant for skin blisters and as an aphrodisiac.