adv. Mus. [It. tranquillo adj. TRANQUIL.] In a tranquil style or tempo; tranquilly.

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1854.  J. Schuberth’s Mus. Hand-bk. (ed. 4), Tranquillamente, Tranquillo, calmly, peacefully, tranquil.

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1889.  Grove, Dict. Mus., Tranquillo, an Italian term, meaning ‘calmly,’ ‘quietly.’

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1905.  Westm. Gaz., 22 April, 12/1. Resting wilt thou Largo play, Presto or Tranquillo?

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