efficax

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.