Definition of fireworm in US English:



  • 1Chiefly poetic. A firefly, a glow-worm. rare.

  • 2US. The larva of any of several small moths of the superfamily Tortricoidea which are pests of the cranberry and other cultivated plants; especially (more fully "black-headed fireworm") the widespread Rhopobota naevana (also called holly tortrix).

  • 3Any of various predatory bristle worms (polychaetes) of the family Amphinomidae, having stinging bristles that can cause severe inflammation; especially (more fully "bearded fireworm") Hermodice carunculata of the tropical Atlantic, Caribbean, and Mediterranean.

  • 4Any of several bristle worms (polychaetes) of the genus Odontosyllis (family Syllidae), which become bioluminescent during the mating period; especially (more fully "Bermuda fireworm") O. enopla of the tropical west Atlantic.


Mid 16th century (in an earlier sense). From fire + worm.