wavelength

noun

wave·​length ˈwāv-ˌleŋ(k)th 

1

: the distance in the line of advance of a wave from any one point to the next point of corresponding phase

2

: a particular course or line of thought especially as related to mutual understanding

two people on different wavelengths

Examples of wavelength in a Sentence

Light and sound have different wavelengths.

Recent Examples on the Web

Additionally, some supermassive black holes form a jet of outflowing material that emits strongly at radio wavelengths. —Georgina Jedikovska, Interesting Engineering, 23 Jan. 2026

This coloring occurs because deep, compact ice absorbs light’s longer wavelengths—like reds and yellows—and scatters shorter blue wavelengths back toward our eyes. —Laura Kiniry, Popular Science, 22 Jan. 2026

EMFs are bad depending on the pulse rates and the wavelengths, and some of them are very bad. —Will Carless, USA Today, 22 Jan. 2026

This process — called Rayleigh scattering — scatters shorter-wavelength blue light and bends longer-wavelength red light toward the moon. —Jamie Carter, Forbes.com, 21 Jan. 2026

Word History

First Known Use

1850, in the meaning defined at sense 1

Kids Definition

wavelength

noun

wave·​length ˈwāv-ˌleŋ(k)th 

1

: the distance (as from crest to crest) in the line of advance of a wave from any one point to the next corresponding point

2

: a certain line of thought or behavior that reveals a common understanding

coworkers who are on the same wavelength

Medical Definition

wavelength

noun

wave·​length -ˌleŋ(k)th 

: the distance in the line of advance of a wave from any one point to the next point of corresponding phase

—symbol λ