What does "luminescence" mean?

Any emission of light that cannot be attributed merely to the temperature of the emitting body.

How do you pronounce "luminescence"?

Pronounced //ˌluː.məˈnɛs.əns//.

Common synonyms include: glow, afterglow, autoluminescence, bioillumination, bioluminescence, cathode luminescence.

/ˌluː.məˈnɛs.əns/ noun

noun ·Uncommon ·Advanced level

Noun

1
Any emission of light that cannot be attributed merely to the temperature of the emitting body. countable, uncountable
2
light from nonthermal sources wordnet
3
light not due to incandescence; occurs at low temperatures wordnet

From Latin lumen + -escence.