spectral width
wavelength interval over which the magnitude of all spectral components is equal to or greater than a specified fraction of the magnitude of the component having the maximum value
en-US/ˈspɛktɹəl ˈwɪdθ/
en-GB/ˈspɛktɹəl ˈwɪdθ/
wavelength interval over which the magnitude of all spectral components is equal to or greater than a specified fraction of the magnitude of the component having the maximum value