doppler shiftOur editors are putting together more complete content — check back in about 20 minutesdoppler shiftdoppler shift — noun名詞1. a change in frequency of a wave, like sound or light, due to movement1.名詞釋義a change in frequency of a wave, like sound or light, due to movement例句The siren's pitch increases because of the Doppler shift as the ambulance approaches.