fireworm noun4 •The bearded fireworm, Hermodice carunculata, a species of polychaete in family Amphinomidae, which may cause pain if touched. •The golden fireworm, Chloeia flava, a species of polychaete. •The larva of any of several tortricid moths (family Tortricidae). •The larva of a small tortricid moth that feeds on cranberry leaves, giving the plant a burnt look; the cranberry worm. formsfireworms