princĭpĭum | princĭpĭa, ōrum (noun N.n) : princeps
* A beginning, commencement, origin (class.; syn.: primordia, initium).
* In gen.: origo principii nulla est: nam ex principio oriuntur omnia,Cic. Tusc. 1, 23, 54: quid est cujus principium aliquod sit, nihil sit extremum?id. N. D. 1, 8, 20: nec principium, nec finem habere,id. Sen. 21, 78: cujus criminis neque principium invenire, neque evolvere exitum possum,id. Cael. 23, 56: hic fons, hoc principium est movendi,id. Rep. 6, 25, 27: bellorum atque imperiorum,id. Balb. 3, 9: principium pontis,Tac. A. 1, 69: principio lucis,at daybreak,Amm. 25, 5, 1: in principiis dicendi,at the commencement of a speech,Cic. de Or. 1, 26, 121; so of a declaration in a lawsuit,Juv. 6, 245: suave quoddam principium dicendi,Amm. 30, 4, 19: principia ducere ab aliquo, to derive, deduce: omnium rerum magnarum principia a dis immortalibus ducuntur,id. Vatin. 6, 14: principium urbis,id. Off. 1, 17, 54: scribendi recte sapere est et principium et fons,Hor. A. P. 309: omne principium huc refer,id. C. 3, 6, 6: a Jove principium,Verg. E. 3, 60: anni,Liv. 1, 4: a sanguine Teucri Ducere principium,Ov. M. 13, 705: capessere,to begin,Tac. A. 15, 49.—Adverb.: principio, a principio, in principio, at or in the beginning, at first: principio ... postea, etc.,Cic. Div. 2, 35, 75: principio generi animantium omni est a naturā tributum, ut se tueatur,id. Off. 1, 4, 11; id. Tusc. 2, 22, 53; id. Fin. 1, 6, 17; Ter. Eun. 5, 8, 39; id. And. 3, 3, 38; Verg. A. 6, 214; Cic. Off. 3, 5, 21; so, a principio: ac vellem a principio te audissem, etc.,id. Att. 7, 1, 2: dixeram a principio, de re publicā ut sileremus,id. Brut. 42, 157: in principio,id. de Or. 1, 48, 210: principio ut,as soon as,Plaut. Merc. prol. 40; v. Ritschl ad h. l.— Rarely of the boundaries of a country or people: adusque principia Carmanorum,Amm. 23, 6, 74.
* In partic.
* Plur., beginnings, foundations, principles, elements (class.): bene provisa et diligenter explorata principia ponantur,Cic. Leg. 1, 13, 37: juris,id. ib. 1, 6, 18: naturae,id. Off. 3, 12, 52; for which: principia naturalia,id. Fin. 3, 5, 17; cf. id. ib. 2, 11, 35: principia rerum, ex quibus omnia constant,first principles, elements,id. Ac. 2, 36, 117.— Prov.: obsta principiis (cf. the French: ce n'est que le premier pas qui coute),Ov. R. Am. 91.
* That makes a beginning, that votes first: tribus principium fuit, pro tribu Q. Fabius primus scivit, Lex Thoria, Rudorff. p. 142; Lex Appar. ap. Haubold, Moment. Leg. p. 85; Plebissc. ap. Front. Aquaed. 129: Faucia curia fuit principium,was the first to vote,Liv. 9, 38 fin.
* In gen., a beginner, originator, founder, ancestor (poet.): Graecia principium moris fuit,Ov. F. 2, 37: mihi Belus avorum Principium,ancestor, progenitor,Sil. 15, 748.—Here, too, prob. belongs PRINCIPIA SACRA, Aeneas and his successors in Lavinium, ancestors whom the Latins and Romans honored as deities, Inscr. Orell. 2276.
* In milit. lang.:
* The foremost ranks, the front line of soldiers, the front or van of an army: post principia,behind the front,Liv. 2, 65; cf.: hic ero post principia, inde omnibus signum dabo,Ter. Eun. 4, 7, 11: post principia paulatim recedunt, Sisenn. ap. Non. 135, 31: deinde ipse paulatim procedere; Marium post principia habere,Sall. J. 50, 2: traversis principiis, in planum deducit,id. ib. 49, 6: equites post principia collocat,Liv. 3, 22; Tac. H. 2, 43.
* Precedence, preference, the first place: principium ergo, columenque omnium rerum preti margaritae tenent,Plin. 9, 35, 54, § 106.
* Plur., selections, selected passages: principiorum libri circumferuntur, quia existimatur pars aliqua etiam sine ceteris esse perfecta,Plin. Ep. 2, 5, 12.
* In partic., mastery, dominion (post-class.): ἀρχή, magisterium, magistratus, praesidatus, principium, Gloss. Philox.: in Graeco principii vocabulum, quod est ἀρχή, non tantum ordinativum, sed et potestativum capit principatum, Tert. adv. Hermog. 19.

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