per-tĭnax, ācis, adj. [tenax], that holds fast, that clings firmly, very tenacious.
I Lit. (only poet. and in post-Aug. prose): digitus male pertinax, Hor. C. 1, 9, 24: ales unguibus pertinax, Ap. Flor. p. 366: tenaxne pater ejus est? Ph. Pater immo edepol pertinax, exceedingly avaricious , Plaut. Capt. 2, 2, 39.—
B Transf., that lasts long , very durable : spiritus, Plin. 10, 29, 43, § 81: siligo in Allobrogum agro pertinax, id. 18, 8, 20, § 85.—
II Trop., firm , constant , steadfast , persevering , unyielding; in a bad sense, obstinate , pertinacious , stubborn (cf. pervicax); constr. absol. , with in and abl.; also (rare and not ante-Aug.) with in and acc., adversus and acc., ad and acc.; also (post-Aug.) with gen., Att. ap. Non. 433, 6 sq.: concertationes in disputando pertinaces, Cic. Fin. 1, 8, 27 sq.: pertinacissimus fueris, si, etc., id. ib. 2, 33, 107: valde pertinax, id. ib. 2, 3, 9: pertinax fama, Plin. 24, 17, 101, § 159: studium, Quint. Inst. prooem.: certamen, Liv. 2, 40: stare pertinaci statu, Gell. 2, 1, 2: octoginta milia fortissimae pertinacissimaeque in retinendis armis juventutis, Vell. 2, 27, 1: pertinax virtus, Liv. 25, 14: pertinax adversus temerarios impetus, id. 28, 22, 14: pertinacior in repugnando, id. 29, 33: pertinax ad obtinendam injuriam, id. 29, 1, 17: in quod coepit pertinax et intenta, Sen. Ira, 1, 1, 2.—
β Poet., with inf.: fortuna ... Ludum insolentem ludere pertinax, Hor. C. 3, 29, 51.—
γ With gen.: justitiae, Ap. Mag. p. 338, 34: irae, Val. Max. 6, 3, 3.—Hence, adv.: pertĭnācĭter .
A Very fast or firmly , very tenaciously , persistently : haec ipsa magis pertinaciter haerent, quo deteriora sunt, Quint. 1, 1, 5; Suet. Tib. 74: pertinacius resistere, Plin. 16, 43, 83, § 227: pertinacissime retinere, id. 33, 6, 32, § 100. —
B Constantly , firmly , steadily , perseveringly; obstinately , stubbornly , pertinaciously : pertinaciter liberalibus studiis deditus, Suet. Claud. 40 fin. : pertinaciter in aliquā re manere, Varr. R. R. 1, 20: pertinaciter offensus, Planc. ap. Cic. Fam. 10, 23, 1: contendere, Suet. Caes. 1: studere, Sen. Ep. 5, 1.— Comp. : pertinacius insequi, Hirt. B. G. 8, 13.— Sup. : pertinacissime pabulo abstinere, Suet. Caes. 81 med. ; id. Ner. 56.—
III Pertĭnax , ācis, m., surname of the emperor P. Helvius , who succeeded Commodus on the throne , Capitol. Pert. 1; Aur. Vict. Epit. 18.