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 happens because its light passes through more of Earth's atmosphere, which scatters away the shorter blue wavelengths and lets the longer red tones pass through, an effect known as Rayleigh scattering. —Anthony Wood, Space.com, 9 Apr. 2026

These masks use specific wavelengths of light — red for collagen support and blue for targeting acne bacteria — to address skin concerns at a cellular level. —Lauren Jarvis-Gibson, Kansas City Star, 8 Apr. 2026

These devices use specific wavelengths of light to target common skin concerns, including acne, fine lines and inflammation. —Lauren Jarvis-Gibson, Miami Herald, 8 Apr. 2026

The Laser Interferometer Lunar Antenna (LILA) would close the gap between LIGO and LISA by tuning in to waves with intermediate wavelengths. —Joseph Howlett, Scientific American, 8 Apr. 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