[L., ad. Gr. τρίγωνον triangle: see TRIGON.]
1. Antiq. A musical instrument: = TRIGON 3 c.
1727–41. Chambers, Cycl., s.v. Music, Of stringed instruments we hear of the lyra or cithara, the psalterium, trigonum, sambuca [etc.].
1801. Busby, Dict. Mus., Trigonum, or Triangular Harp, an instrument supposed to have been of Phrygian invention. Ibid. From Sophocles we learn, that a certain musician … was so admirable a performer on the Trigonum,… that [etc.].
2. Anat. = TRIGONE.
1879. St. George’s Hosp. Rep., IX. 322. The walls of the bladder were slightly hypertrophied, and there was a small ulcer on the left half of the trigonum.
