Seismic surface waves travel along the Earth's surface. They can be classified as a form of mechanical surface waves. They are called surface waves, as they diminish as they get further from the surface. They travel more slowly than seismic body waves (P and S). In large earthquakes, surface waves can have an amplitude of several centimeters.
gnaw meaning, definition, what is gnaw: to bite or chew something repeatedly, usually making a hole in it or gradually destroyingâ¦. Learn more.
Gnat, any member of several species of small flies that bite and annoy humans. Several nonbiting insects, such as the midges, which resemble mosquitoes, are also sometimes known as gnats. In North America the name is often applied to the black fly, midge, fungus gnat, biting midge, fruit fly (qq.v.), and other small flies that hover about the eyes of humans and other animals.