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hōrŏlŏgĭum, ĭi, n., = ὡρολόγιον, a clock, horologe, either a sundial or a waterclock, Plin. 2, 76, 78, § 187; 7, 60, 60, § 213; Varr. R. R. 3, 5, 17; Cic. Fam. 16, 18, 2; Vitr. 9, 8 sq.; Inscr. Orell. 2032; 3298 sq.