Main Entry: Dopp·ler

Pronunciation: \ˈdäp-lər\

Function: adjective

1 : of, relating to, or utilizing a shift in frequency in accordance with the Doppler effect
2 : of, relating to, using, or produced by Doppler ultrasound <a Doppler examination> <Doppler images>

Doppler, Christian Johann (1803–1853), Austrian physicist and mathematician. Doppler first described the Doppler effect in 1842. It is used in astronomical measurements and in radar and modern navigation. He also investigated the colors in double stars and the effect of rotation of objects on the properties of light and sound waves.