Doppler

American

[dop-ler] / ˈdɒp lər /

noun

Christian Johann, 1803–53, Austrian physicist: discovered the Doppler effect.

Doppler Scientific

/ dŏp′lər /

Austrian physicist and astronomer who in 1842 explained the effect, now named for him, of variations in the frequency of waves as a result of the relative motion of the wave source with respect to the observer.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Doctors and nurses with Doppler machines and ultrasounds kept showing up, forcing them to hear the heartbeat and see the movement of a tiny body.

From Salon • May 27, 2026

A system called Trackman uses in-stadium, two-directional Doppler radar and synchronized high-speed cameras to quantify everything from a ball’s rotation and velocity to location.

From The Wall Street Journal • Apr. 30, 2026

Transcranial Doppler ultrasound tracks how quickly blood travels through the brain's major arteries.

From Science Daily • Feb. 24, 2026

“At 8:53 a.m. Doppler radar indicated thunderstorms producing heavy rain across the warned area,” an alert warned.

From Los Angeles Times • Dec. 25, 2025

The discovery of the Big Bang and the recession of the galaxies came from a commonplace of nature called the Doppler effect.

From "Cosmos" by Carl Sagan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023