Also 4–9 in Lat. form trisagium; also 9 trishagion; also in masc. form trisagios. [a. Gr. (τὸ) τρισάγιον, the eucharistic hymn, neut. of τρισάγιος thrice holy, f. τρίς thrice + ἄγιος holy.] An ancient hymn, used especially in the Oriental Churches, beginning with a threefold invocation of God as holy. Also loosely applied to the ‘angelic hymn’ called TER-SANCTUS or SANCTUS, q.v.
1387. Trevisa, Higden (Rolls), V. 11. He ordeyned þat trisagium, þat is, ‘Sanctus, sanctus, sanctus,’ schulde be songe at masse.
1635. Pagitt, Christianogr., 99. The Trisagion being solemnly sung, the Copt Priest beginneth the Consecration.
1654–6. Trapp, Comm. Isa. vi. 1. The prophet Isaiah … heareth the trisagion of the blessed angels.
1710. Wheatley, Bk. Com. Prayer, vi. § 19. Of the Trisagium.
a. 1711. Ken, Christophil, Poet. Wks. 1721, I. 483. O may I with Seraphick Heat Trisagions while I live repeat.
1885. Notes on Angels, 56. In the Tris-Hagion or Ter Sanctus of the Communion Office.
1894. F. Watson, Bk. Genesis true Hist., v. 89. He [Isaiah] hears the Seraphim chanting the Trisagion.
