Efficax, pe. cor. huius, efficâcis, om. g. Plin. Effectual: of strength: force, or power: that can doe much.Efficacius ad rectè viuendum. Pl. iu. Of more efficacy, or force to honest life.Efficaces ad muliebre ingeniÛ preces. Li. Praiers effecteous and much preuailing with womens natures.Efficax aduersus serpentes. Plin. Contra sagittarum ictus efficacissimum. Pli. Of great force.Efficacissima auxilia. Plin. Helpes of great efficacie.Tardus & parum efficax homo. Cæl. ad Ciceronem. A slacke man and bringing little to effect, or doing, nothing effectually.Efficax vir. Hora. A valiant and strong man able to atchieue that he taketh in hand.
Lewis and Short: Latin dictionary
effĭcax, ācis, adj. [efficio], efficacious, effectual, powerful, efficient (mostly postAug.; not in Cic. and Caes; but cf. efficacitas): nosti Marcellum, quam tardus et parum efficax sit, Cael. ap. Cic. Fam. 8, 10, 3; cf.: ultor contemptae religionis, Val. Max. 1, 1, 19: Hercules, Hor. Epod. 3, 17: scientia (magica), id. ib. 17, 1: preces, Liv. 9, 20: studium promerendi amoris, Suet. Calig. 3 init.: breve et efficax iter est per exempla, Sen. Ep. 6, 5: admonitiones, id. ib. 8, 2 al.: herba in dolore stomachi, Plin. 27, 13, 109, 136: preces ad muliebre ingenium, Liv. 1, 9 fin.; so with ad, Sen. Ben. 2, 7 fin.; cf. in the comp., Quint. 6, 1, 41; Plin. Pan. 84: elatine oculorum fluxionibus efficax, Plin. 27, 9, 50, 74; so with dat., id. 28, 14, 58, 204; in the sup.: continuatio in peragendis rebus, Liv. 41, 15: frutex efficacissimus contra sagittarum ictus, Plin. 13, 21, 36, 115; cf.: herba adversus serpentium venena, id. 24, 15, 80, 130: ad excitandam virtutem, etc., Vell. 1, 8, 1. —Poet., with inf.: (cadus) amara Curarum eluere efficax, Hor. C. 4, 12, 20; Val. Max. 2, 7, 10: cum sit efficacissimum de integro locum exarare, Col. 2, 17, 3: efficacissimum est hic quoque salem superponere, Cels. 4, 4, 16; 4, 22, 11.—Hence, adv.: effĭcācĭter, effectually, powerfully, Quint. 5, 13, 25; Sen. Brev. Vit. 6 et saep.—Comp., Quint. 8, 4, 8; Tac. G. 8; Plin. Ep. 6, 6, 8; Plin. 24, 6, 14, 23.— Sup., Plin. 26, 12, 79, 128; 24, 6, 14, 23; id. Ep. 2, 13 fin.
