[L. trīduum, prop. neut. of *trīduus adj. (sc. spatium), f. tri-, TRI- + diēs day.] a. A period of three days; esp. in R. C. Ch. the last three days of Lent. b. = TRIDUO.
1883. Schaff, Hist. Church, II. XI. lxxi. 525. The mysterious triduum between the crucifixion and the resurrection.
1885. Pall Mall G., 7 Nov., 7/2. Yesterday there commenced at the Church of the Servite Fathers … a Triduum to celebrate an event of interest in the early history of our Royal family.
1910. Universe, 3 June, 9/1. A solemn Triduum in honour of the feast of Corpus Christi was preached in St. Mary’s Cathedral, Edinburgh.
