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

One of the trademarks of healthy skin is a radiant complexion—and the best sunscreens for glowing skin are game-changers for achieving luminosity while protecting your skin from dangerous UV rays. —Annie Blackman, Allure, 9 Apr. 2025

British laws require certain luminosity levels, precise positioning and specific visibility angles of headlights. —Peter Lyon, Forbes, 20 Feb. 2025

Andrew credits high-gloss Benjamin Moore Gray Owl paint for doing a lot to visually enhance the ceiling height and add luminosity. —Kathryn Romeyn, Architectural Digest, 19 Feb. 2025

The array of explosions also varied in terms of luminosity, which will aid researchers in their search for answers to dark energy and the acceleration of the universe. —Jack Knudson, Discover Magazine, 14 Feb. 2025

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

Rhymes for luminosity

• adiposity

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