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

• brilliance
• brilliancy
• candor
• dazzle
• effulgence
• illumination
• lambency
• lightness
• luminance
• luminosity
• luminousness
• luster
• lustre
• lustrousness
• radiance
• refulgence
• splendor

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

The upper-right-hand side of the bar has two areas: one includes the equivalent of notification tray icons, and the other offers quick access to screen brightness, network connection, sound, and Dark Style settings. —PCMAG, 14 Feb. 2025

But everyone agreed that Girard’s best quality was its brightness—that zing of acidity that balanced its salty, savory bite. —Sam Stone, Bon Appétit, 13 Feb. 2025

The moon reached its peak brightness at 8:53 a.m. EST (1353 GMT) on Feb. 12, but local moonrise and moonset times will depend on your location. —Daisy Dobrijevic, Space.com, 12 Feb. 2025

Last to arrive are Rick (Walton Goggins) and Chelsea (Aimee Lou Wood), a couple whose attachment to one another is hard to parse given his disinterest in her and her youthful, inextinguishable brightness toward him. —Ben Travers, IndieWire, 11 Feb. 2025

Word History

First Known Use

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

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