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 planet and star will be at almost equal brightness and their color contrast will be striking. —Joe Rao, Space.com, 24 Dec. 2024

And the eclipse ends as the moon returns to normal brightness at 4:47 a.m. —Dean Regas, The Enquirer, 19 Dec. 2024

Since then, Apple has released two subsequent Series generations, with the Series 9 doubling the screen brightness and adding gesture controls, and the Series 10 introducing a more refined design with a bigger display that's easier to read at off angles. —PCMAG, 12 Dec. 2024

Hubble has studied the size and the brightness of this concentration for years, though how atmospheric flow and other factors control its seasonal changes is still uncertain. —Sam Walters, Discover Magazine, 12 Dec. 2024

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