Doppler

American  

[dop-ler] / ˈdɒp lər /

noun

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

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Doppler Scientific  

/ dŏp′lər /

1. 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.

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Example Sentences

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

Bilateral lower extremity venous Doppler ultrasounds were performed and revealed chronic venous insufficiency, a benign and common condition, particularly in individuals over the age of 70.

From Slate • Jul. 18, 2025

Deep Sea Vision had first put to sea in September 2023 from Papua New Guinea, launching a $9-million Hugin 6000 submersible equipped with a Doppler, a magnetometer, an echo sounder and a side-scan sonar.

From Los Angeles Times • Nov. 8, 2024

But in 1845, Doppler had loaded a train with a band of trumpet players and asked them to hold a note as the train sped forward.

From "The Gene" by Siddhartha Mukherjee