brightness

noun

bright·​ness ˈbrīt-nəs 

1

a

: the quality or state of being bright

also : an instance of such a quality or state

b

: luminance

2

: the attribute of light-source colors by which emitted light is ordered continuously from light to dark in correlation with its intensity compare hue sense 2c, lightness entry 1 sense 2a, saturation sense 4

Synonyms of brightness

• brilliancy
• brilliance
• lightness
• illumination
• luminosity

Examples of brightness in a Sentence

the brightness of the sunshine made me squint after an afternoon spent in a darkened movie theater

Recent Examples on the Web

And, to a large extent, Chicago third baseman Miguel Vargas, who lost two battles with the brightness and paved the way for Bader’s game-changing grand slam. —Justice Delos Santos, Mercury News, 23 May 2026

The screen also offers up to 350 nits of brightness, making the colors pop out and the blacks and whites contrast nicely. —George Yang, PC Magazine, 23 May 2026

Brighten up a dark entryway or add a warm glow to your bedroom with multiple brightness settings and a variety of color temperatures to get the ambiance just right. —Caley Sturgill, Southern Living, 23 May 2026

How does its brightness compare now with full? —Joe Rao, Space.com, 22 May 2026

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1a

Rhymes for brightness

• lightness
• rightness
• tightness
• whiteness
• finiteness
• politeness
• uprightness

Medical Definition

brightness

noun

bright·​ness ˈbrīt-nəs 

: the one of the three psychological dimensions of color perception by which visual stimuli are ordered continuously from light to dark and which is correlated with light intensity compare hue, saturation sense 4a