A seismic body wave propagated in the crust or mantle of the earth by a shearing motion of material; speed is 1.9-2.5 miles (3-4 kilometers) per second in the crust and 2.7-2.9 miles (4.4-4.6 kilometers) in the mantle. Also known as distortional wave; equivoluminal wave; rotational wave; secondary wave; shake wave; shear wave; tangential wave; transverse wave.