Wavenumber in most physical sciences is a wave property inversely related to wavelength, having SI units of reciprocal meters (m−1). Wavenumber is the spatial analog of frequency, that is, it's the measurement of the number of repeating units of a propagating wave (the number of times a wave has the same phase) per unit of space. Application of a Fourier transformation on data as a function of time yields a frequency spectrum; application on data as a function of position yields a wavenumb… (More on Wavenumber)