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

noun, plural lu·mi·nos·i·ties.

the quality of being intellectually brilliant, enlightened, inspired, etc.: The luminosity of his poetry is unequaled.
something luminous.
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 luminous flux to radiant flux at that wavelength.

Origin of luminosity

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

Related forms

non·lu·mi·nos·i·ty, nounself-lu·mi·nos·i·ty, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for luminosity

British Dictionary definitions for luminosity


/ (ˌluːmɪˈnɒsɪtɪ) /

noun plural -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 observedFormer name: brightness See also colour
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012