Incandescence/ˌɪnkənˈdesns/ Definition 1 of 2Pro Tip 1/3Heat Emission Incandescence is used to describe light from objects heated until they glow. The incandescence of the coal embers illuminated the dark room. Pro Tip 2/3Not Burning An object's incandescence doesn't mean it's on fire; just extremely hot. We saw the metal's incandescence but there were no flames. Pro Tip 3/3Natural Phenomenon Use 'incandescence' when describing light from natural objects without flames. The incandescence of lava flows is visible at night.