efficacia
From LSJ
διὰ νήσων τὸν πλόον ἐποιεῦντο → they kept sailing through the islands
Latin > English (Lewis & Short)
effĭcācĭa: ae, f. efficax,
I efficacy, efficiency, virtue (post-Aug.), Plin. 11, 5, 4, § 12; Amm. 14, 8, 5; 16, 12, 25; Vulg. Sirach, 9, 4; Lact. de Ira D. 10, 37.
Latin > French (Gaffiot 2016)
effĭcācĭa, æ, f. (efficax), puissance efficace, propriété : Plin. 11, 12 : Amm. 14, 8, 5.