Alfv¿n waves propagating outward from the coronal base set the solar wind into oscillatory motion. The effect of this wave motion on the broadening and shape of the spectral lines of the resonantly scattered Ly &agr; radiation emitted by a low-density coronal hole is investigated at hights above 1.5 RS from Sun center. Usually it has been assumed that the broadening due to waves can be characterized by a kinetic temperature proportional to the wave velocity amplitude squared, Δv2. It is shown that the accuracy of this approximation depends on the wave velocity amplitude and the assumed wave spectrum. ¿ American Geophysical Union 1990