a. and sb. Mus. Also (masc.) terzo. [It. terza, fem. of terzo third:—L. tertia.] a. adj. The third, as in opera terza, the third work; violino terzo, third violin. b. sb. A third; also in terza, in three parts; terzo = TRIO.

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1724.  Short Explic. For. Wds. in Mus. Bks., Terza, a Third…. Opera Terza,… Violina Terza. Ibid., In Terza,… Songs or Tunes in Three Parts, the same as Trio below.

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