different between effectual vs efficacy

English

Alternative forms

• effectuall (obsolete)

Etymology

From Old French effectuel, from Late Latin effectualis.

Pronunciation

• IPA^(key): /i?f?kt?u?l/

Adjective

effectual (comparative more effectual, superlative most effectual)

1. Producing the intended result; entirely adequate.

Antonyms

• ineffectual

Derived terms

• effectualization
• effectualize

Related terms

English

Etymology

From Old French efficace, from Late Latin effic?cia (“efficacy”), from effic?x (“efficacious”); see efficacious.

Pronunciation

• IPA^(key): /??f.?.k?.si/

Noun

efficacy (usually uncountable, plural efficacies)

1. Ability to produce a desired effect under ideal testing conditions.
   • 2005, Flay et al. Standards of Evidence: Criteria for Efficacy, Effectiveness and Dissemination DOI: 10.1007/s11121-005-5553-y

     Efficacy refers to the beneficial effects of a program or policy under optimal conditions of delivery, whereas effectiveness refers to effects of a program or policy under more real-world conditions.

2. Degree of ability to produce a desired effect.
   • 1996, Moskovich, Patent application PCT/US1996/003658

     Toothbrush with improved efficacy

Synonyms

• efficacity

Related terms

Translations

Further reading

• efficacy in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.
• efficacy in The Century Dictionary, New York, N.Y.: The Century Co., 1911.