(adjective) : arduus, a, um, akin to ΑΡΔΩ, ἄρσω = to water, to cherish; ἀλδαίνω = to make grow; ἀλδήεις = growing; alo, altus, q. v.; 1. ad-oleo, ad-olesco; related to arbor, arbutus as ἐρυθρός, Germ. roth, Engl. red, is related to ruber; Ardea was perh. so called from its lofty situation; cf. Arduenna
* High, elevated, lofty, steep (syn.: altus, celsus, sublimis).
* Lit.: Pergama ardua, Enn. ap. Macr. S. 6, 2: aether,Ov. M. 1, 151: sidera,id. ib. 1, 730: cedrus,id. Am. 1, 14, 12: cervix equi,Hor. S. 1, 2, 89: et campo sese arduus infert (Turnus),Verg. A. 9, 53.—Also in prose in Gell.: supercilia,i. e. proudly elevated,Gell. 4, 1, 1: confragosus atque arduus clivis,steep,Varr. R. R. 1, 18, 4: ascensus,Cic. Verr. 2, 4, 23: arduus ac difficilis ascensus,Liv. 25, 13: ardua et aspera et confragosa via,id. 44. 3: via alta atque ardua, Enn. ap. Cic. Tusc. 1, 16, 37: mons,Ov. M. 1, 316: Tmolus,id. ib. 11, 150 al.—Hence, subst.: arduum, i, n., a steep place, a steep: Ardua dum metuunt, amittunt vera viaï,Lucr. 1, 659: in ardua montis Ite,Ov. M. 8, 692: ardua terrarum,Verg. A. 5, 695: per arduum scandere,Hor. C. 2, 19, 21: in arduo,Tac. A. 2, 47: in arduis ponet nidum suum,Vulg. Job, 39, 27: ardua Alpium,Tac. H. 4, 70: castellorum,id. A. 11, 9: ingressi sunt ardua,Vulg. Jer. 4, 29.
* Trop.
* That is difficult to reach or attain, difficult, laborious, hard, arduous: magnum opus omnino et arduum conamur,Cic. Or. 10, 33: rerum arduarum ac difficilium perpessio,id. Inv. 2, 54; so id. Leg. 1, 13: id arduum factu erat,Liv. 8, 16; Tac. A. 4, 4: victoria,Ov. M. 14, 453: virtus,Hor. C. 3, 24, 44: nil mortalibus arduum est,id. ib. 1, 3, 37.—Subst.: nec fuit in arduo societas,Tac. A. 12, 15.
* Troublesome, unpleasant: in primis arduum videtur res gestas scribere,Sall. C. 3, 2, upon which Gellius remarks: Arduum Sallustius non pro difficili tantum, sed pro eo quoque ponit, quod Graeci χαλεπὸν appellant: quod est cum difficile tum molestum quoque et incommodum et intractabile,Gell. 4, 15: quam arduum onus,Tac. A. 1, 11.
* Of fortune, difficult, adverse, inauspicious: aequam memento rebus in arduis Servare mentem,in adversity,Hor. C. 2, 3, 1.!*? Comp. arduior: iter longius arduiusque erat, Cato ap. Prisc. p. 600 P.—Sup. arduissimus: asperrimo atque arduissimo aditu, Cato ap. Prisc. p. 600 P.; cf.: assiduus, egregius, industrius, perpetuus, and Rudd. I. p. 180, n. 58.—Adv. not used.

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