Efficacious

• POS: Adjective
• HYPHEN: ef=fi=ca=cious

CIDE DICTIONARY

Efficacious, 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.

OXFORD DICTIONARY

Efficacious, adj. (of a thing) producing or sure to produce the desired effect.

Derivative

efficaciously adv. efficaciousness n. efficacy n.

Etymology

L efficax (as EFFICIENT)

THESAURUS

Efficacious

able, active, adequate, authoritative, capable, charismatic, charming, competent, consequential, effective, effectual, efficient, enchanting, equal to, estimable, functional, go, important, influential, magnetic, momentous, operational, operative, personable, persuasive, potent, powerful, practical, prestigious, productive, proficient, puissant, reputable, serviceable, strong, suasive, substantial, successful, telling, up to, useful, virtuous, weighty, winning

ROGET THESAURUS

Efficacious

Utility

N utility, usefulness, efficacy, efficiency, adequacy, service, use, stead, avail, help, applicability, subservience, function, value, worth, money's worth, productiveness, cui bono, utilization, step in the right direction, common weal, commonwealth public good, public interest, utilitarianism, useful, of use, serviceable, proficuous, good for, subservient, conducive, subsidiary, advantageous, profitable, gainful, remunerative, worth one's salt, valuable, prolific, adequate, efficient, efficacious, effective, effectual, expedient, applicable, available, ready, handy, at hand, tangible, commodious, adaptable, of all work, usefully, pro bono publico.

Power

N power, potency, potentiality, jiva, puissance, might, force, energy, dint, right hand, right arm, ascendency, sway, control, prepotency, prepollence, almightiness, omnipotence, authority, strength, ability, ableness, competency, efficacy, efficiency, productivity, expertise (skill), validity, cogency, enablement, vantage ground, influence, pressure, conductivity, elasticity, gravity, electricity, magnetism, galvanism, voltaic electricity, voltaism, electromagnetism, atomic power, nuclear power, thermonuclear power, fuel cell, hydraulic power, water power, hydroelectric power, solar power, solar energy, solar panels, tidal power, wind power, attraction, vis inertiae, vis mortua, vis viva, potential energy, dynamic energy, dynamic friction, dynamic suction, live circuit, live rail, live wire, capability, capacity, quid valeant humeri quid ferre recusent, faculty, quality, attribute, endowment, virtue, gift, property, qualification, susceptibility, powerful, puissant, potential, capable, able, equal to, up to, cogent, valid, efficient, productive, effective, effectual, efficacious, adequate, competent, multipotent, plenipotent, omnipotent, almighty, forcible, (energetic), influential, productive, powerfully, by virtue of, by dint of, a toute force, dos moi pou sto kai kino ten gen, eripuit coelo fulmen sceptrumque tyrannis, fortis cadere cedere non potest.

Agency

N agency, operation, force, working, strain, function, office, maintenance, exercise, work, swing, play, interworking, interaction, procurement, causation, instrumentality, influence, action, modus operandi, quickening power, maintaining power, sustaining power, home stroke, operative, efficient, efficacious, practical, effectual, at work, on foot, acting, in operation, in force, in action, in play, in exercise, acted upon, wrought upon, by the agency of through, by means of, I myself must mix with action lest I wither by des.