luminous

adjective

lu·​mi·​nous ˈlü-mə-nəs 

1

a

: emitting or reflecting usually steady, suffused, or glowing light

… luminous objects—the nebula, the stars, the planets …

—Lincoln La Paz

b

: of or relating to light or to luminous flux

2

: bathed in or exposed to steady light

luminous with sunlight

3

: clear, enlightening

a luminous explanation

4

: shining, illustrious

a luminous film star

a luminous performance

luminously adverb

luminousness noun

Did you know?

Luminous, like its synonyms radiant, shining, glowing, and lustrous, is generally a positive adjective, especially when it describes something that doesn't literally glow, such as a face, a performance, or a poem. Luminous signs depend on a gas such as neon, krypton, argon, xenon, or radon—and you can use luminous (DayGlo) paint to make your own signs. New technologies have now given us luminous fabrics, which are being used to produce striking or creepy effects in clothing, upholstery, and interior surfaces.

Synonyms of luminous

• glowing
• shining
• dazzling
• bright
• radiant
• shiny
• brilliant
• shimmering
• gleaming
• sparkling
• lustrous

Choose the Right Synonym for luminous

bright, brilliant, radiant, luminous, lustrous mean shining or glowing with light.

bright implies emitting or reflecting a high degree of light.

brilliant implies intense often sparkling brightness.

radiant stresses the emission or seeming emission of rays of light.

luminous implies emission of steady, suffused, glowing light by reflection or in surrounding darkness.

lustrous stresses an even, rich light from a surface that reflects brightly without glittering.

Examples of luminous in a Sentence

I saw the cat's luminous eyes in my car's headlights.

a watch with a luminous dial

The room was luminous with sunlight.

Recent Examples on the Web

Two streetlamps engaged in a mute but luminous dialogue, an indecipherable Morse code, alluding to the silent exchanges and secret ciphers of strangers who meet there for their trysts. —Javier Montes, Artforum, 1 Jan. 2026

Best viewed from the Northern Hemisphere, the ideal time to get outside and try to spot some of these luminous fireballs is in the predawn hours on January 4, according to NASA. —Claire Cameron, Scientific American, 1 Jan. 2026

At this positioning, Jupiter will look larger and more luminous in the night sky, National Geographic said. —Hannah Poukish, Sacbee.com, 30 Dec. 2025

Her blond slick hair frames her face, falls naturally on her shoulders and makes a luminous spot on her dark outfit. —Tonya Blazio-Licorish, Footwear News, 29 Dec. 2025

Word History

Etymology

Middle English luminouse, luminose, borrowed from Anglo-French & Latin; Anglo-French luminous, borrowed from Latin lūminōsus "full of light, dazzling," from lūmin-, lūmen "light, source of light" + -ōsus -ous — more at lumen

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing luminous

• luminous energy
• luminous flux
• luminous paint
• self-luminous

Rhymes for luminous

• numinous
• albuminous
• aluminous
• bituminous
• leguminous
• voluminous
• subbituminous

Kids Definition

luminous

adjective

lu·​mi·​nous ˈlü-mə-nəs 

1

: giving off light : shining

2

: being lighted

a public square luminous with sunlight

3

: clear entry 1 sense 3

luminous writing

4

: illustrious

luminously adverb

luminousness noun

Medical Definition

luminous

adjective

lu·​mi·​nous ˈlü-mə-nəs 

1

: emitting or reflecting usually steady, suffused, or glowing light

2

: of or relating to light or to luminous flux