Efficacious — Ef fi*ca cious, a. [L. eficax, acis, fr. efficere. See {Effect}, n.] Possessing the quality of being effective; productive of, or powerful to produce, the effect intended; as, an efficacious law. Syn: See {Effectual}. {Ef fi*ca cious*ly}, adv.… … The Collaborative International Dictionary of English
efficacious — [ef΄i kā′shəs] adj. [L efficax (gen. efficacis) < efficere, to bring to pass, accomplish (see EFFECT) + OUS] producing or capable of producing the desired effect; having the intended result; effective [an efficacious drug] SYN. EFFECTIVE… … English World dictionary
efficacious — sure to have the desired effect (often of medicines), 1520s, from L. efficaci , stem of efficax (see EFFICACY (Cf. efficacy)) + OUS (Cf. ous). Related: Efficaciously; efficaciousness … Etymology dictionary
efficacious — effectual, *effective, efficient Analogous words: potent, *powerful, puissant: cogent, telling, sound, convincing, compelling (see VALID) Antonyms: inefficacious: powerless … New Dictionary of Synonyms
efficacious — [adj] efficient, productive active, adequate, capable, competent, effective, effectual, energetic, influential, operative, potent, powerful, puissant, serviceable, strong, successful, useful, virtuous; concepts 528,537 Ant. incapable,… … New thesaurus
efficacious — ► ADJECTIVE formal ▪ effective. DERIVATIVES efficaciously adverb efficaciousness noun. ORIGIN from Latin efficere accomplish … English terms dictionary
efficacious — effective, effectual, efficacious, efficient 1. All these words mean ‘having an effect’ of some kind, but with different applications and shades of meaning. Effective means ‘having a definite or desired effect’ that is actual rather than… … Modern English usage
efficacious — [[t]e̱fɪke͟ɪʃəs[/t]] ADJ GRADED Something that is efficacious is effective. [FORMAL] The nasal spray was new on the market and highly efficacious. Syn: effective … English dictionary
efficacious — adjective Etymology: Latin efficac , efficax, from efficere Date: 1528 having the power to produce a desired effect < an efficacious remedy > Synonyms: see effective • efficaciously adverb • efficaciousness noun … New Collegiate Dictionary
efficacious — efficaciously, adv. efficaciousness, n. /ef i kay sheuhs/, adj. capable of having the desired result or effect; effective as a means, measure, remedy, etc.: The medicine is efficacious in stopping a cough. [1520 30; < L efficaci (s. of efficax)… … Universalium