noun. An electrically neutral excited state of an insulator or semiconductor, often regarded as a bound state of an electron and a hole.

noun. A bound state of an electron and an electron hole in an insulator or semiconductor

"So far, they have only managed to prevent one type of quenching called exciton-metal quenching, which was done by moving the light-emitting area further away from the electrodes."

excitonic  excitonically  excitonics  orthoexciton  paraexciton