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efficacious

efficacious

7 8.6
Able to produce the desired result
  • adjective
  • /ˌɛfɪˈkeɪʃəs/
  • Formal
translation icon : eficaz
  • The water inside the pillar was efficacious for diseases of vision and for fertility.
  • efficacious treatment
  • efficacious intervention
  • the most efficacious

It is so efficacious so I put it on.

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Examples

  • Thus, these findings provide preliminary evidence that culturally specific interventions are more efficacious than generic interventions.

    Academic text (2008)
  • Your presence will be efficacious.

  • One, it's safe and efficacious and we make a gazillion dollars.

  • It's incredible to know that there are clean, non-toxic products that are really efficacious and really work wonders on your skin.

  • Neither treatment was significantly more efficacious, which we believe is due to our high-quality implementation of these two treatments.

    Academic text (2008)
  • We have a strong rationale for why SOFT should be an efficacious treatment model for adolescents who abuse substances.

    Academic text (2008)
  • Topical azelaic acid and metronidazole are considered safe and efficacious first-line therapies.

    Academic text (2015)
  • Many people find that exercise is an efficacious way to reduce stress and improve mental health.

  • The researchers concluded that their new method was efficacious in promoting faster recovery from the illness.

  • After several trials, the team discovered a vaccine that was highly efficacious in preventing the disease.

Synonyms

effective
vsefficacious
986 3.1

Produces the intended result, for example a speech or medicine

has the power to cause the intended result rather than just succeeding
effectual
vsefficacious
1 6.8

Able to produce the intended result

focuses on having power to produce that outcome
supereffective
vsefficacious
6.7

Very good at making something work much better than usual

means having power to produce the intended effect without extra intensity

Antonyms

90 3.4

Not working well enough to give the wanted result

Not effective at making the result you want

How Effective

potent
119 5.5
efficacious
  • Formal
7 8.6
effective
986 3.1
limited
162 2.0
ineffective
90 3.4

Surface Forms

efficacious positive
efficacier comparative
efficaciest superlative

Morphology

efficacious = efficacy (semi-transparent) = efficacy + ous

Formally derived from 'efficacy' with a stem/spelling change (y -> i) and a Latinate formation, so the relation is regular but not obvious to many learners.

Etymology

Efficacious comes from a Latin word efficere, made of ex- meaning 'out' and facere meaning 'to do'. So if something is efficacious, it 'brings about' or produces the result you want, just like the English words effect and effective show.