Wavelength

wavelength
(Science: radiobiology) The length of a single cycle of a wave, usually measured from crest-to-crest. For electromagnetic waves, the wavelength determines the type (radio, infrared, visible, ultraviolet, x-Ray, gamma–ray) of radiation, in the case of visible light, wavelength determines the colour of the light.
The distance (measured in the direction of propagation) between two points in the same phase in consecutive cycles of a wave.A measurement between two successive points of a wave, which can be used to measure things like light and sound. The wavelength of lights’ visible to the human eye range from violet (400 nanometres) to red (750 nanometres).