different between efficacious vs effectiveness

English

Etymology

From Old French efficacieux, from Latin effic?x (“efficacious”) +? -ous, from efficere (“to effect, to accomplish”); see effect.

Pronunciation

• IPA^(key): /?f.?.?ke?.??s/

  Rhymes: -e???s

Adjective

efficacious (comparative more efficacious, superlative most efficacious)

1. (formal) Effective; possessing efficacy. [from 1520s]

   Synonym: effective

   Antonym: inefficacious

Related terms

Translations

Further reading

• efficacious in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.
• efficacious in The Century Dictionary, New York, N.Y.: The Century Co., 1911.
• “efficacious”, in Lexico, Dictionary.com; Oxford University Press, 2019–present.

English

Etymology

effective +? -ness

Pronunciation

Noun

effectiveness (countable and uncountable, plural effectivenesses)

1. The property of being effective, of achieving results.

   The effectiveness of the drug was well established.

2. The capacity or potential for achieving results.
3. The degree to which something achieves results.

   He questioned the effectiveness of the treatment.

   • 2013, Phil McNulty, "[1]", BBC Sport, 1 September 2013:

     United were having more possession but a sign of the effectiveness of Liverpool's defence was that it took the visitors 76 minutes to force Mignolet into serious action, when he dived to punch away a shot from substitute Nani.

Related terms

• effect
• effective
• effectivity
• effector
• effectual
• effectuate
• efficacious
• efficacity
• efficacy
• efficiency
• efficient

Translations