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bidŭus, a, um, adj. [bis-dies], continuing two days, of two days; as adj. only once, with tempus, Liv. 27, 24, 3, where tempus is prob. to be omitted; v. Weissenb. ad loc. But very freq. and class. as subst.: bīdŭum, ii, n. (sc. tempus), a period or space of two days, two days: sinito biduom aut triduom consudent (oves), Cato, R. R. 96, 1: biduum supererat, Caes. B. G. 1, 23; Ter. And. 2, 6, 9; Planc. ap. Cic. Fam. 10, 17: in castra quae aberant bidui (sc. spatio), id. Att. 5, 16, 4; 5, 17, 1; cf. id. ib. 8, 14, 1: eximant unum aliquem diem aut summum biduum ex mense, id. Verr. 2, 2, 52, § 129: rus ibo: ibi hoc me macerabo biduum, Ter. Eun. 1, 2, 101 sq.; 2, 2, 52; 4, 2, 8; Cic. Att. 8, 14, 1; Nep. Att. 22, 3; Tac. A. 3, 13; 3, 17: supplicationes in biduum decretae, Liv. 10, 23, 1: per biduum, Cic. N. D. 2, 38, 96; Quint. prooem. 7: per insequens biduum, Liv. 30, 8, 4: uno die longior mensis aut biduo, Cic. Verr. 2, 2, 52, § 129: biduo et duabus noctibus Adrumetum pervenit, Nep. Hann. 6, 3: biduo post, Suet. Caes. 16; so Caes. B. G. 1, 47 init.: post biduum, Suet. Caes. 43; id. Aug. 10: biduo continenti, id. Calig. 19; Tac. A. 11, 8; 14, 32.