1. plural of luminosity; the quality or state of giving off light; brightness
2. plural of luminosity; in astronomy, the total amount of energy radiated by a star or other celestial body per unit time
Usage: astronomy

Examples

• The luminosities of the different stars varied dramatically across the night sky.
• Scientists measured the luminosities of several distant galaxies.
• The luminosities of these LED bulbs are much higher than traditional incandescent ones.
• Astronomers compare stellar luminosities to understand star formation.
• The luminosities recorded by the telescope revealed previously unknown celestial objects.
• Different types of stars have characteristic luminosities based on their mass and age.