A review is given of theoretical and experimental papers on the interaction of acoustic waves with spin waves in ferridielectrics. The region of the resonance interaction -- the magnetoacoustic resonance (MAR), in which the interaction is synchronous and is most effective, is discussed in greatest detail. Considerable attention is devoted to nonlinear magnetoacoustic resonance -- i.e. to detection of MAR not by absorption, but by generation of higher harmonics of the acoustic wave. The review also discusses the possibilities of using MAR for studying the magnetic and defect structures of crystalline ferridielectrics. The review encompasses practically all the basic papers in this field. The experimental results are systematized, and their correspondence with theory is analyzed.