Prices 2018 - Wavenumber Units, K is for wavenumber — agile, K is for wavenumber. wavenumber , sometimes called the propagation number, is in broad terms a measure of spatial scale. it can be thought of as a spatial analog to the temporal frequency, and is often called spatial frequency. it is often defined as the number of wavelengths per unit distance, or in terms of wavelength, λ:. Wavenumber to wavelength conversion | sciencing, Wavenumbers may be expressed in different units, notably cm − 1.if you have a wavenumber in a different unit, you can convert it to a wavelength in the same way as in the previous section.. What is the unit for wavenumber - answers.com, Wavenumber is the spatial analog of frequency, that is, it is the measurement of the number of wavelengths per unit distance, or more commonly 2π times that, or the number of radians of phase per ..