a. and sb. Also 7 tryenniall, triennuall, 8 trienial. [f. L. trienni-s of three years, trienni-um a space of three years (f. tri-, TRI- + annus year) + -AL. Cf. prec.]
A. adj. 1. Existing or lasting for three years, three-years’; changed every three years.
Triennial Act (Eng. Hist.), an act of 1640, limiting the duration of parliament to three years; also the name given to an act of 1694, following an earlier one of Charles II., providing against any longer intermissions of parliament than three years Cf. sense 2.
1640. Jrnls. Ho. Comm., II. 83. Amendments … to the Bill of Triennial Parliaments.
1643. Prynne, Sov. Power of Parl., II. 25. The Admiralls Patents (which anciently were … but annuall or Triennuall at most).
c. 1645. Howell, Lett. (1650), I. 70. My friends, whom I so much long to see after this triennial separation.
1701. Lond. Gaz., No. 3756/9. Whenever the Dissolution of this Present … Parliament shall happen, either by Virtue of the Trienial Act, or Prerogative Royal.
1807. Horsley, Serm. (1812), II. 316. We, in the writings of the evangelists have a complete summary of his [Christ’s] triennial preaching.
1863. H. Cox, Instit., I. vi. 35. The Triennial Act of William III limited the duration of Parliament to three years at the furthest.
2. Recurring every three years.
1642. Howell, For. Trav. (Arb.), 77. If these Lights grow dim, there is a Trienniall Snuffer for them.
1663. Blair, Autobiog., v. (1848), 77. Primate Usher’s triennial visitation.
1782. T. Warton, Hist. Kiddington, 8. To the bishop for Procurations, on account of his triennial visitation.
1821. Miss Mitford, in L’Estrange, Life (1870), II. vi. 140. We have been very gay … with our triennial theatricals.
1872. Yeats, Growth Comm., 182. There was a triennial change of officers.
B. sb. 1. A period of three years; a triennium.
1661. Sir H. Vane’s Politics, 13. During our Principality, which breathed out many Triennials.
1892. Min. Nat. Counc. Congr. Ch. (U. S.), 143. No other triennial in the history of the society has a tithe of the work in the way of … printed appeals.
2. An event recurring every three years; spec. the visitation of his diocese by a bishop every three years.
1640. Archdeaconry of Essex Minutes, 29 July (MS.). We were this day inhibited for the Bp’s. of London’s tryenniall, by Gilson.
1724. Bp. Downes, in Nicolson’s Epist. Corr., 576. The expence of the Triennial may leave your pocket empty.
Hence Trienniality [cf. F. triennalité], the condition of being triennial.
1806. W. Taylor, in Ann. Rev., IV. 240. The parliament … produced fewer great men during its trienniality, than since the prolongation.
1817. Bentham, Parl. Reform, Introd. (1818), 283. Moderate reform insists at stopping at the stage indicated by the word trienniality.
