luminosity

noun

lu·​mi·​nos·​i·​ty ˌlü-mə-ˈnä-sə-tē 

plural luminosities

1

a

: the quality or state of being luminous

b

: something luminous

2

a

: the relative quantity of light

b

: relative brightness of something

3

: the relative quantity of radiation emitted by a celestial source (such as a star)

Synonyms

• brightness
• brilliance
• brilliancy
• candor
• dazzle
• effulgence
• illumination
• lambency
• lightness
• luminance
• luminousness
• luster
• lustre
• lustrousness
• radiance
• refulgence
• splendor

Examples of luminosity in a Sentence

the luminosity of the fireflies made for an enchanting nighttime show

Recent Examples on the Web

The quasar's luminosity outshines the brightest giant elliptical galaxies by over tenfold. —Paul Du Quenoy, Newsweek, 9 Dec. 2024

Pink and gold pearl add luminosity, while the brand's signature blend of green tea, rice, and algae delivers hydration. —Annie Blackman, Allure, 29 Nov. 2024

Make sure lights are compatible with the space (indoor vs. outdoor) and that the luminosity matches the power voltage or surge protector. —Kait Hanson, Southern Living, 28 Nov. 2024

Despite its gargantuan size, this galaxy's active galactic nucleus is classified as low luminosity. —Dan Perry, Newsweek, 26 Nov. 2024

Word History

Etymology

borrowed from Middle French & Medieval Latin; Middle French luminosité, borrowed from Medieval Latin lūminōsitāt-, lūminōsitās, from Latin lūminōsus "full of light, luminous" + -itāt-, -itās -ity

First Known Use

1634, in the meaning defined at sense 1a

Kids Definition

luminosity

noun

lu·​mi·​nos·​i·​ty ˌlü-mə-ˈnäs-ət-ē 

plural luminosities

1

: the quality or state of being luminous : brightness

2

: something luminous

Medical Definition

luminosity

noun

lu·​mi·​nos·​i·​ty ˌlü-mə-ˈnäs-ət-ē 

plural luminosities

1

: the quality or state of being luminous

2

a

: the relative quantity of light

b

: the comparative degree to which light of a given wavelength induces the sensation of brightness when perceived