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

The team uses its spectroradiometer to capture data across 2,151 wavelength bands from a small spot on a leaf for a reading. —Abhimanyu Ghoshal, New Atlas, 21 Nov. 2025

Previously, researchers observed that ice samples exposed to UV light for short periods absorbed different wavelengths than those exposed for hours. —Mrigakshi Dixit, Interesting Engineering, 21 Nov. 2025

As starlight filters through a planet’s atmosphere, different molecules absorb specific wavelengths of light, leaving behind a chemical fingerprint that reveals which gases are present. —Morgan Underwood, The Conversation, 19 Nov. 2025

But if there is a redshift, then the observed wavelength will be longer than the emitted wavelength, and the amount of lengthening is what corresponds to redshift. —Big Think, 19 Nov. 2025

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