[fahyuh
r-wurm] 
| 1. | the larva of any of several moths, as Rhopobota naevana (black-headed fireworm), which feeds on the leaves of cranberries and causes them to wither. |
| 2. | glowworm. |
fireworm
any of certain segmented marine worms of the class Polychaeta (phylum Annelida), including species of the genera Hermodice and Eurythoe. Fireworms produce a stinging sensation if touched. The body of H. carunculata, found in the coral reefs of the Caribbean Sea, is covered with fine, white, brittle bristles that break if touched; they easily become imbedded in human skin and produce a substance that is highly irritating.
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