Noun
stationary wave (plural stationary waves)
A wave form which occurs in a limited, fixed medium in such a way that the reflected wave coincides with the produced wave. A common example is the vibration of the strings on a musical stringed instrument.
Mathematical description In one dimension, two waves with the same frequency, wavelength and amplitude traveling in opposite directions will interfere and produce a standing wave or stationary wave. Source: Internet
The red dots represent the wave nodes A standing wave, also known as a stationary wave, is a wave that remains in a constant position. Source: Internet