flutter

v. flap, wave; (about the heart) beat; vibrate, tremble, quiver; confuse, agitate; run about aimlessly

n. flapping or fluttering movement; agitated state, nervousness, excitedness; commotion; abnormally fast heartbeat; rapid change in pitch

In electronics and communication, flutter is the rapid variation of signal parameters, such as amplitude, phase, and frequency. In structures, the term refers to rapid periodic motion caused by interaction of structural mass, stiffness, and aerodynamic forces.Examples of flutter are:Rapid variations in received signal levels, such as variations that may be caused by atmospheric disturbances, antenna movements in a high wind, or interaction with other signals.In radio propagation, a phenomenon in which nearly all radio signals that are usually reflected by ionospheric layers in or above the E-region experience partial or complete absorption.In radio transmission, rapidly changing signal levels, together with variable multipath time delays, caused by reflection and possible partial absorption of the signal by aircraft flying through the radio beam or common scatter volume.The variation in the transmission characteristics of a loaded telephone circuit caused by the action of telegraph direct currents on the loading coils.In recording and reproducing equipment, the deviation of frequency caused by irregular mechanical motion, e.g., that of capstan angular velocity in a tape transport mechanism, during operation.
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Flutter /flut·ter/ a rapid vibration or pulsation. atrial flutter cardiac arrhythmia in which the atrial contractions are rapid, but regular. [more]Flutter - Community and Resources

Noun
1. the act of moving back and forth
(synonym) waver, flicker
(hypernym) motion, movement, move, motility
(derivation) flicker, waver, flitter, quiver
2. abnormally rapid beating of the auricles of the heart (especially in a regular rhythm); can result in heart block
(hypernym) cardiac arrhythmia, arrhythmia
(derivation) palpitate
3. a disorderly outburst or tumult; "they were amazed by the furious disturbance they had caused"
(synonym) disturbance, disruption, commotion, stir, hurly burly, to-do, hoo-ha, hoo-hah, kerfuffle
(hypernym) disorder
(hyponym) convulsion, turmoil, upheaval
4. the motion made by flapping up and down
(synonym) flap, flapping, fluttering
(hypernym) wave, undulation
Verb
1. move along rapidly and lightly; skim or dart
(synonym) flit, fleet, dart
(hypernym) travel rapidly, speed, hurry, zip
(hyponym) butterfly
(derivation) waver, flicker
2. move back and forth very rapidly; "the candle flickered"
(synonym) flicker, waver, flitter, quiver
(hypernym) move back and forth
(derivation) waver, flicker
3. beat rapidly; "His heart palpitated"
(synonym) palpitate
(hypernym) beat, pound, thump
(verb-group) palpitate
4. wink briefly; "bat one's eyelids"
(synonym) bat
(hypernym) blink, wink, nictitate, nictate

n. flutter, flapping or fluttering movement, agitated state