(Also called ripple, capillary ripple.) A wave for which the primary restoring force is surface tension; generally taken to be one of less than 1.7-cm wavelength, this being the wavelength for which the theoretical phase speed is a minimum, and marking the transition from gravity to surface tension as the dominant restoring force at the sea surface. Compare gravity wave.
A capillary wave is a wave travelling along the interface between two fluids, whose dynamics are dominated by the effects of surface tension. Capillary waves are common in nature and the home and are often referred to as ripples. The wavelength of capillary waves is typically less than about a centimeter.