S waves are known as secondary wave or shear waves
Explanation;
Seismic wave are types of waves that result from break down of rocks within the earth or an explosion. Seismic waves are classified as body waves and surface waves.
Body waves are classified into either secondary waves or primary waves. Commonly known as the S-waves and the P-waves.
Secondary waves are types of body waves that move through an object's body unlike the case of surface waves. It is the second wave that is felt after an earthquake.
