doppler_effect has definitions from the field of physics
1
[ noun ] (physics) change in the apparent frequency of a wave as observer and source move toward or away from each other

Synonyms

Doppler_shift

Used in print

(Walter H. Buchsbaum, "Advances in Medical Electronics"...)

The Doppler_effect , using ultrasonic signals , can be employed to measure the flow of blood without cutting into the blood_vessel .

Related terms

propagation red_shift

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