The glow of a fire is known as incandescence. If you see a shooting star, the bright light is due to incandescence. When you have a good idea, a cartoon light bulb goes on over your head – incandescence can refer to that kind of lighting up, too, like a brilliant idea that sheds light on something. If someone has a thousand-watt smile, that’s incandescence. Any time something lights up from heat, physically or emotionally, it produces incandescence.