luminosity

American  

[loo-muh-nos-i-tee] / ˌlu məˈnɒs ɪ ti /

noun

luminosities plural

1. luminance.

2. the quality of being intellectually brilliant, enlightened, inspired, etc..

   The luminosity of his poetry is unequaled.

3. something luminous.

4. Astronomy. the brightness of a star in comparison with that of the sun: the luminosity of Sirius expressed as 23 indicates an intrinsic brightness 23 times as great as that of the sun.

5. Also called luminosity factor.  Optics. the brightness of a light source of a certain wavelength as it appears to the eye, measured as the ratio of luminous flux to radiant flux at that wavelength.

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luminosity British  

/ ˌluːmɪˈnɒsɪtɪ /

noun

1. the condition of being luminous

2. something that is luminous

3. astronomy a measure of the radiant power emitted by a star

4. Former name: brightness.  physics the attribute of an object or colour enabling the extent to which an object emits light to be observed See also colour

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Other Word Forms

Derived Forms

• nonluminosity
  noun
• self-luminosity
  noun

Inflected Forms

Nouns

• luminosities
  plural

Etymology

Origin of luminosity

1625–35; < Latin lūminōs ( us ) luminous + -ity

Explanation

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."

Example Sentences

See Examples For:

luminosity luminosities

The goal is to increase the "luminosity" -- that is, the total number of collisions produced over a given period -- by a factor of 10 compared to the LHC.

From Barron's ● Jun. 27, 2026

“I have no medium that can give me color of such wonderful luminosity as the Autochrome plate,” wrote the photographer Edward Steichen in 1908.

From The Wall Street Journal ● Nov. 21, 2025

A follow-up spectrum from the W. M. Keck Observatory in Hawai'i revealed the AGN's extreme luminosity.

From Science Daily ● Nov. 7, 2025

In the Rhapsody, though, Kim delivered incisive accompaniment without interfering with Kantorow’s sophisticated luminosity.

From Los Angeles Times ● Jan. 29, 2025

I must have felt pretty weird by that time because I could think of nothing except the luminosity of his pink suit under the moon.

From " The Great Gatsby" by F. Scott Fitzgerald

High-sensitivity observations have discovered objects with extremely high X-ray luminosities.

From Science Daily ● Dec. 14, 2025

The lower luminosities of red dwarf stars also means their habitable zones -- the range of orbital distances where liquid water could exist on a planet's surface -- lie closer to them.

From Science Daily ● May 23, 2024

Suvi Gezari, an astronomer at the Space Telescope Science Institute, says the observations extend the phenomenon of red novae to much lower luminosities and into the regime of planetary engulfments.

From Science Magazine ● May 3, 2023

The brutal fury of a system like WR 140 is undeniable, from the incredible luminosities of its stars to the cosmic tsunami of dusty winds they blast away.

From Scientific American ● Oct. 25, 2022

In ordinary wet or dry plate photography these effects would have been reversed, but by Dixon and Gray’s process the relative luminosities of these three colours were almost perfectly translated.

From The Evolution of Photography With a Chronological Record of Discoveries, Inventions, etc., Contributions to Photographic Literature, and Personal Reminescences Extending over Forty Years by Werge, John