12 letters · 18 points in Scrabble
noun light not due to incandescence; occurs at low temperatures
noun light from nonthermal sources
originEtymology tree Latin lumen Proto-Indo-European *-éh₁ti Proto-Indo-European *-sḱéti Proto-Indo-European *-éh₁sḱeti Proto-Italic *-ēskō Latin -ēscō Latin -escensder. English -escence English luminescence From Latin lumen + English -escence.
Etymology from Wiktionary, CC BY-SA 3.0