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

Different elements and molecules absorb light at specific wavelengths, so studying the spectrum of starlight that has passed through an atmosphere can reveal a great deal about that atmosphere's composition. —Mike Wall, Space.com, 10 Jan. 2026

At these heights, telescopes can detect light at much longer and shorter wavelengths, which are otherwise blocked by Earth’s atmosphere. —Martin Elvis, The Conversation, 9 Jan. 2026

Television is built on repetition, and anthology series in particular rely on recognizable set-ups to keep audiences on the same wavelength, season after season, new cast after new cast. —Christian Zilko, IndieWire, 7 Jan. 2026

As the sun and moon agitate, your ego and emotions are on different wavelengths! —Usa Today, USA Today, 5 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