nŭdĭusnum (i. e. nunc) and dius = dies; the ending accommodated to that of the following numeral
* It is now the ... day since, always in connection with ordinal numbers; as, nudius tertius, three days ago, the day before yesterday: nudius quartus, four days ago, etc.: nudius tertius videtur compositum ex nunc et die et tertio, Paul. ex Fest. p. 170 Müll.: heri et nudius tertius, Quartus, quintus, sextus, etc.,Plaut. Most. 4, 2, 40: nam ego Lemno advenio Athenas nudius tertius,id. Truc. 1, 1, 74: nudius sextus quoi talentum mutuom dedi reposcam,id. Trin. 3, 2, 101; cf. Afran. ap. Charis. p. 192 P.: nudius tertius dedi ad te epistulam longiorem,Cic. Att. 14, 11, 1; here, nudius quintus natus quidem ille est,Plaut. Truc. 2, 6, 28: recordamini, qui dies nudius tertiusdecimus fuerit,Cic. Phil. 5, 1, 2: a nudius quartā die,Vulg. Act. 10, 30.