A seismic wave that travels relatively quickly through the earth, causing the rocks it passes through to change shape, and the particles of the rocks to vibrate at right angles to the direction of wave propagation. S-waves can travel through solids but not through liquids or gases.
Wave motion in a solid medium in which the particles of the medium oscillate in a direction perpendicular to the direction of travel of the wave: it cannot be transmitted through a fluid.
The definition of an S wave, or secondary wave, is a wave motion in a solid medium where the medium moves perpendicular to the direction of the travel of the wave.
An example of an S wave is when pieces of rock in an earthquake vibrate at right angles to the direction of the seismic wave.
Origin of s-wave
S(econdary) wave since it is the second type of wave, after the faster P-waves, to be detected by a seismograph after a seismic event.