Vibrato

n. tremulous musical effect caused by rapid changes in pitch

Vibrato is a musical effect, produced in singing and on musical instruments by a regular pulsating change of pitch, and is used to add expression and vocal-like qualities to instrumental music.
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Noun
1. (music) a pulsating effect in an instrumental or vocal tone produced by slight and rapid variations in pitch
(hypernym) sound
(hyponym) tremolo
(classification) music

n. vibrato, tremulous effect (Music)

n. vibrato, tremulous musical effect caused by rapid changes in pitch