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vibrato vs. tremolo

[vi-brah-toh, vahy-] / vɪˈbrɑ toʊ, vaɪ- /

noun

Music.

plural

vibratos
  1. a pulsating effect, produced in singing by the rapid reiteration of emphasis on a tone, and on bowed instruments by a rapid change of pitch corresponding to the vocal tremolo.

[trem-uh-loh] / ˈtrɛm əˌloʊ /

noun

Music.

plural

tremolos
  1. a tremulous or vibrating effect produced on certain instruments and in the human voice, as to express emotion.

  2. a mechanical device in an organ by which such an effect is produced.