[loo-muh-nos-i-tee] /ˌlu məˈnɒs ɪ ti/
noun, plural luminosities.
the quality of being intellectually brilliant, enlightened, inspired, etc.:
The luminosity of his poetry is unequaled.
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.
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 to radiant flux at that wavelength.
noun (pl) -ties
the condition of being luminous
something that is luminous
(astronomy) a measure of the radiant power emitted by a star
(physics) the attribute of an object or colour enabling the extent to which an object emits light to be observed Former name brightness See also colour
1630s, “quality of being luminous,” from French luminosité or else a native formation from luminous + -ity. In astronomy, “intrinsic brightness of a heavenly body” (as distinguished from apparent magnitude, which diminishes with distance), attested from 1906.
noun, Astronomy. 1. a classification of stars of a given spectral type according to their luminosity, breaking them down into dwarfs, giants, and supergiants.
[loo-muh-nuh s] /ˈlu mə nəs/ adjective 1. radiating or reflecting light; shining; bright. 2. lighted up or illuminated; well-lighted: the luminous ballroom. 3. brilliant intellectually; enlightened or enlightening, as a writer or a writer’s works: a luminous concept; luminous prose. 4. clear; readily intelligible: a concise, luminous report. /ˈluːmɪnəs/ adjective 1. radiating or reflecting light; […]
noun, Optics. 1. the perceived brightness of light as a ratio of the total luminous flux to total radiant flux of the source; a measure of brightness obtained by dividing the source’s luminous flux by the consumption of its energy. noun 1. the efficiency of polychromatic radiation in producing a visual sensation. It is the […]
noun, Optics. 1. luminous flux emitted per unit area.