(Science: zoology) a coleopterous insect of the genus Lampyris; especially, the wingless females and larvae of the two European species (L. Noctiluca, and L. Splendidula), which emit light from some of the abdominal segments. Like a glowworm in the night, The which hath fire in darkness, none in light. (Shak)
The male is winged, and is supposed to be attracted by the light of the female. In America, the luminous larvae of several species of fireflies and fire beetles are called glowworms. Both sexes of these are winged when mature. See firefly.