Above: single K giant star's spectrum; Below: galaxy bulge spectrum. Notice (a) the redshift of the galaxy; (b) the fact that all the absorption features in the galaxy are smoothed relative to the K giant. The shift gives the average velocity (including, redshift in this case), and the amount of smoothing gives the velocity dispersion. This spectral region contains a number of relatively strong narrow absorption lines and so is useful for measuring velocity dispersions. The integrated light in this galaxy is a close match to a K star.
The top spectra in each panel is a single K star, and the spectra below are from the central regions of galaxies (AGN in this case). In all cases, the galaxy absorption lines are "broadened" relative to the K star, some more than others. Left spectra in the Mg-triplet region, Right spectra in the Ca-triplet region.