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

Changes in the spacecraft's velocity will appear in the Doppler shift of those radio signals, allowing engineers to quickly determine Psyche's updated speed and trajectory after it departs Mars and continues toward the asteroid belt.

From Science Daily • May 11, 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

Named for Johann Christian Doppler, an Austrian physicist, who first noticed the effect in 1842.

From "A Short History of Nearly Everything" by Bill Bryson