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

• 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

Magnitude Magnitude is the scale used to measure the apparent brightness of objects in the night sky. —Anthony Wood, Space.com, 17 Oct. 2025

So why doesn’t Logano just conform to the more pessimistic outlook instead of trying to infuse others with brightness? —Jeff Gluck, New York Times, 17 Oct. 2025

The power/brightness of the two barrels can be controlled simultaneously or independently via one-touch button controls. —Ben Coxworth october 17, New Atlas, 17 Oct. 2025

Visually, the screen impresses with strong brightness, vivid contrast, and rich color reproduction. —PC Magazine, 15 Oct. 2025

Word History

First Known Use

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

Rhymes for brightness

• lightness
• rightness
• tightness
• whiteness
• 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