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1. excĭdĭum (sometimes written exscidium, as if from exscindo), ii, n. [usually referred to ex-cīdo], overthrow, demolition, subversion, ruin (especially of cities, buildings, etc.), destruction (not freq. till the Aug. per.; not in Caes. and Cic.): urbis, Liv. 27, 39 fin.; Tac. H. 1, 80; 3, 76; Verg. A. 5, 626.
In plur.: petit urbem excidiis, Verg. G. 2, 505; id. A. 2, 643; 10, 46; Liv. 9, 45; 29, 1 al.: castellorum, Tac. H. 4, 15: arcium, Verg. A. 12, 655: Libyae, id. ib. 1, 22: gentium, Vell. 2, 98, 2; Tac. H. 5, 25; cf. Cretensium, Sall. H. Fragm. p. 290 ed. Gerl.: legionum, Tac. H. 4, 61: meorum, Verg. A. 8, 386 et saep.
2. excĭdĭum, ii, n. [excĭdo], a going down, setting: solis, Prud. Apoth. 694.