Rayleigh waves, also known as the Rayleigh-Lamb Wave or "ground roll", are a type of surface wave. They are associated on the Earth with earthquakes and subterranean movement of magma, or with any other source of seismic energy, such as an explosion or even a sledgehammer impact, and are also the form of ocean waves.

From a condensed matter physics point of view Rayleigh waves are surface acoustic waves and associated with a huge number of electronic components, the SAW devices, which employ them. SAW devices are mainly used in cellular phones and wireless technology, and their worldwide yearly production is approximated to lie over 1 billion .