tremolo

Tre"mo*lo, n. Etym: [It. Cf. Tremulous.] (Mus.) (a) The rapid reiteration of tones without any apparent cessation, so as to produce a tremulous effect. (b) A certain contrivance in an organ, which causes the notes to sound with rapid pulses or beats, producing a tremulous effect; -- called also tremolant, and tremulant.

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