phosphorescence (noun) – the emission of light without perceptible heat
BREAKDOWN: PHOS- (light) + PHOR- (bring) + -ESCENCE (quality of)
— phosphorescent means exhibiting phosphorescence
This word is built on the root PHOR-, which means to bear, bearing, or bring.
Common PHOR- words include metaphor, pheromone, and phosphorescent.
More esoteric PHOR- words include dysphoric.