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

This blacklight flashlight uses a 395nm wavelength to detect what the naked eye—or a traditional flashlight—cannot. — Aly Walansky, Travel + Leisure, 22 Sep. 2026

This is to allow the Vectis to diminish its radar signal across a number of wavelength bands. — New Atlas, 20 Sep. 2026

The first is that JWST, looking at wavelengths where almost no occultation has ever been recorded, is simply seeing grains that scatter light differently in the infrared. — Jacek Krywko, ArsTechnica, 19 Sep. 2026

In 2025, researchers at the institute developed an all-solid-state DUV laser capable of producing 193nm coherent light, the wavelength used by advanced DUV lithography systems. — Bojan Stojkovski, Interesting Engineering, 19 Sep. 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