luminosity

/ˈluməˌnɑsədi/

Other forms: luminosities

Luminosity is the quality of something that gives off light or shines with reflected light. The most noticeable quality of a large, sparkly diamond is its luminosity.

You might describe a bright and lively oil painting in terms of its luminosity, or marvel at the luminosity of a brilliant sunset. Astronomers use the word luminosity to talk about a specific property of physics, the energy given of by an astronomical object in a certain amount of time. There's a direct correlation between this amount of energy and the object's brightness. The Latin root is lumen, meaning "light."

Definitions of luminosity

1. noun

   the quality of being luminous; emitting or reflecting light
   “its luminosity is measured relative to that of our sun”

   synonyms: brightness, brightness level, light, luminance, luminousness

   types:

   illuminance, illumination

   the luminous flux incident on a unit area

   incandescence

   light from heat

   glow, luminescence

   light from nonthermal sources

   type of:

   physical property

   any property used to characterize matter and energy and their interactions