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a. Emitting light, especially in the dark; shining.
b. Reflecting light; illuminated: "He watched a luminous cloud drifting up from the Gulf" (Tim Gautreaux). See Synonyms at bright.
2. Having a high degree of saturation: a luminous green.
a. Presented or perceived clearly or vividly: luminous memories.
b. Enlightened or intelligent: luminous ideas.

[Middle English, from Old French lumineux, from Latin lūminōsus, from lūmen, lūmin-, light; see leuk- in Indo-European roots.]

lu′mi·nous·ly adv.
lu′mi·nous·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.luminousness - the quality of being luminousluminousness - the quality of being luminous; emitting or reflecting light; "its luminosity is measured relative to that of our sun"
physical property - any property used to characterize matter and energy and their interactions
illuminance, illumination - the luminous flux incident on a unit area
incandescence - light from heat
glow, luminescence - light from nonthermal sources
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in classic literature ?
"Let us consider a little each of these characters in succession, and first (for of the shafts enough has been said already), what is very peculiar to this church--its luminousness."
The pallor of his countenance had assumed, if possible, a more ghastly hue--but the luminousness of his eye had utterly gone out.
Heidegger is dismissive of the decadent present but reverential of the healing character and luminousness of Being, whose solitary prophet Heidegger paints himself as.
The word conveys a dual meaning, evoking both Akari's luminousness and seeming weightlessness, much as the lights merge a duality of traditions, uniting craft with technology through the simple act of inserting an electrical bulb into a form usually illuminated by candlelight.
This infinite universe of "endless perfectnesse," in which the angels' "selves can not endure his [God's] sight" for sheer luminousness (An hymne of heavenly beautie 105, 118-119; Spenser 1959: 597), is in opposition with the image in another writing by Spenser, Ruins of Rome, in which we find a vision of deep open Abysses, of darkest hell, of Great Babylon, of the "worlds' inconstancie" (3: 40), of the temporal fight lasting 36,000 years (22: 304), a vision of the bands of elements returning to their primordial strife, and of the seeds of creation returning to the matrix of chaos:
The attachment to fact in turn underwrites Ruskin's tenet of distinctness in art, a tenet directly antithetical to that of obscurity, so frequently the quality of the Romantic sublime: "in general all great drawing is distinct drawing; for truths which are rendered indistinctly might, for the most part, as well not be rendered at all" (5:60), and again, "generally speaking, all haste, slurring, obscurity, indecision, are signs of low art, and all calmness, distinctness, luminousness, and positiveness, of high art" (5:61).
Under the luminousness of real vision, it alone takes possession, takes value.