[en] An expansion of the collision integral with retardation in terms of multipoles of the deformation of the Fermi surface is obtained. It is shown that the attenuation of zero sound depends on all the multipolarities of the deformation of the Fermi surface. At zero-sound velocities that are large compared with the Fermi velocity the relaxation time is related to the quadrupole deformation of the Fermi surface. The collision contribution to the total widths of nuclear giant multipole resonances is calculated in the semiclassical model. 25 refs., 3 figs