What are waves that go out from an earthquakes epicenter called They rock from side to side quickly?

The waves that radiate out from an earthquake's epicenter and move side to side are called secondary waves, or S-waves. These waves are a type of seismic wave that travels through the Earth and are known for their shear motion, which causes the ground to shake laterally. S-waves can only travel through solid materials and are slower than primary waves (P-waves), which are compressional.