luciferin

noun1

1. •
   Any of a class of polycyclic heterocycles that are responsible for the bioluminescence of fireflies, being converted to oxyluciferin by luciferase in the process.

   • Aptly enough, glowworms light up their underworld with a pair of chemicals that have a satanic etymology—luciferins and luciferases, after the Latin for “light bringer.” — 2017