Synonyms for efficacy
ˈɛf ɪ kə sief·fi·ca·cy

WiktionaryRate these synonyms:0.0 / 0 votes

1. efficacynoun

   Synonyms:
   efficacity

2. efficacynoun

   Ability to produce a desired amount of a desired effect.

   Synonyms:
   efficacity

English Synonyms and AntonymsRate these synonyms:3.6 / 5 votes

1. efficacy

   Power is the most general term of this group, including every quality, property, or faculty by which any change, effect, or result is, or may be, produced; as, the power of the legislature to enact laws, or of the executive to enforce them; the power of an acid to corrode a metal; the power of a polished surface to reflect light. Ability is nearly coextensive with power, but does not reach the positiveness and vigor that may be included in the meaning of power, ability often implying latent, as distinguished from active power; we speak of an exertion of power, but not of an exertion of ability. Power and ability include capacity, which is power to receive; but ability is often distinguished from capacity, as power that may be manifested in doing, as capacity is in receiving; one may have great capacity for acquiring knowledge, and yet not possess ability to teach. Efficiency is active power to effect a definite result, the power that actually does, as distinguished from that which may do. Competency is equal to the occasion, readiness prompt for the occasion. Faculty is an inherent quality of mind or body; talent, some special mental ability. Dexterity and skill are readiness and facility in action, having a special end; talent is innate, dexterity and skill are largely acquired. Our abilities include our natural capacity, faculties, and talents, with all the dexterity, skill, and readiness that can be acquired. Efficacy is the power to produce an intended effect as shown in the production of it; as, the efficacy of a drug. Efficiency is effectual agency, competent power; efficiency is applied in mechanics as denoting the ratio of the effect produced to the power expended in producing it; but this word is chiefly used of intelligent agents as denoting the quality that brings all one's power to bear promptly and to the best purpose on the thing to be done. Compare ADDRESS; DEXTERITY; SKILFUL.

   Synonyms:
   ability, aptitude, capability, capacity, cleverness, cogency, competency, dexterity, efficiency, energy, expertness, faculty, force, might, power, qualification, readiness, skill, strength, susceptibility, talent

   Antonyms:
   awkwardness, dulness, feebleness, helplessness, imbecility, impotence, inability, inaptitude, incapacity, incompetence, inefficiency, maladroitness, stupidity, unskilfulness, weakness

Complete Dictionary of Synonyms and AntonymsRate these synonyms:0.0 / 0 votes

1. efficacy

   Synonyms:
   efficiency, competency, virtue, agency, capability, usefulness, energy, productiveness, effectiveness

   Antonyms:
   inefficiency, inutility, ineffectiveness

Princeton's WordNetRate this synonym:1.0 / 1 vote

1. efficacy, efficaciousnessnoun

   capacity or power to produce a desired effect

   "concern about the safety and efficacy of the vaccine"

   Synonyms:
   efficaciousness

   Antonyms:
   inefficaciousness, inefficacy

Matched Categories

1. • Effectiveness

Editors ContributionRate these synonyms:0.0 / 0 votes

1. capable

   able to do

   Submitted by rinat on August 15, 2019  

Dictionary of English SynonymesRate these synonyms:0.0 / 0 votes

1. efficacynoun

   Synonyms:
   potency, competency, power, strength, force, efficiency

Synonyms, Antonyms & Associated WordsRate these synonyms:5.0 / 1 vote

1. efficacynoun

   Synonyms:
   potency, effectiveness, efficiency, productiveness

   Antonyms:
   inefficacy, impotency

PPDB, the paraphrase databaseRate these paraphrases:0.0 / 0 votes

1. List of paraphrases for "efficacy":

   effectiveness, efficiency, effective, efficient, efficiencies

Suggested Resources

1. Efficacy

   Efficacy vs. Efficiency -- In this Grammar.com article you will learn the differences between the words Efficacy and Efficiency.

How to pronounce efficacy?

How to say efficacy in sign language?

Usage in printed sourcesFrom: 

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Words popularity by usage frequency

How to use efficacy in a sentence?

1. Trevor Bedford:

   You could imagine some modest hit to vaccine efficacy, which wouldn't be good, but I don't think it will break the vaccine.

2. Silvia Taylor:

   We believe fundamentally that people want a choice in the vaccines that they're able to have for themselves, and especially in this population that we're talking about for children, so, we think that that kind of reassuring technology platform that's understood, combined with the high levels of efficacy and the well-tolerated safety profile, can help increase that vaccination number in children.

3. Alex Azar:

   Two vaccines, each with 95 % efficacy, rivaling the 98 % efficacy of our measles vaccine. Produced in some of the largest vaccine clinical trials ever conducted in history. Over 40,000 patients in each of these clinical trials demonstrating good safety profiles.

4. Justin Beck:

   The FDA has been diligent in avoiding political pressure by maintaining a balance of speed to market and obtaining data sufficient to provide emergency use authorization, while we cant yet confirm the long-term efficacy or safety of COVID-19 vaccines, there is enough data to confirm at least three are safe and effective.

5. Paul Stoffels:

   What we are learning is there is different efficacy in different parts of the world.