effectiveness

noun

Definition of effectivenessnext
1
as in conclusiveness
the capacity to persuade the "guilty" verdict was all the proof needed of the effectiveness of the prosecutor's closing argument

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms
2
as in efficacy
the power to produce a desired result the huge upsurge in sales pretty much demonstrated the effectiveness of the new ad campaign

Synonyms & Similar Words

Antonyms & Near Antonyms
3
as in impact
the quality of an utterance that provokes interest and produces an effect your writing lacks effectiveness because practically every sentence is in the passive voice

Synonyms & Similar Words

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of effectiveness The idea would be to equip all parties, from payers to providers to patients, with insights into effectiveness, cost, and value. — Dana P. Goldman, STAT, 22 Oct. 2026 Other topical treatments—such as retinoids, peptides, and vitamin C—are backed by years of research on safety and effectiveness. — Ashley Abramson, Allure, 22 Oct. 2026 Taken together, these reasons have led me to optimistically conclude that the effectiveness of vote buying depends not on the party machine’s prowess but on the strength of the parties that oppose it. — Kenneth Greene, The Conversation, 21 Oct. 2026 Further testing would need to examine venom neutralization, safety, stability, and therapeutic effectiveness before clinical development could be considered. — Neetika Walter, Interesting Engineering, 20 Oct. 2026 Useful measures include remediation of critical exposures, control effectiveness, incident response, release failures and recurring delivery blockers. — Manny Khan, Forbes.com, 20 Oct. 2026 But let’s put cost-effectiveness aside and just truly talk about performance. — Jasmin Malik Chua, Footwear News, 20 Oct. 2026 In my own experience, for some years a pattern of negative thinking undermined my effectiveness at work. — The Christian Science Monitor, Christian Science Monitor, 19 Oct. 2026 That recommendation went against the scientific conclusion of FDA’s staff scientists, who reiterated that none of the peptides had been studied enough to establish their safety and effectiveness. — ABC News, 15 Oct. 2026
Recent Examples of Synonyms for effectiveness
  1. conclusiveness
  2. efficacy
  3. impact
  4. validity
  5. importance
  6. strength
  7. significance
  8. authority
Noun
  • On Friday morning, Burke’s defense team tried to sow doubt about the conclusiveness of the autopsy conducted in the case.
    — Richard Winton, Los Angeles Times, 24 July 2026
  • But his dictionary, with its conclusiveness, was a huge publishing success.
    — Louis Menand, New Yorker, 22 Dec. 2025
Definition of conclusiveness
Noun
  • Huynh described the phase 3 results as clinically meaningful and likely to support regulatory approval, but said the primary efficacy result landed at the low end of investor expectations.
    — Annika Kim Constantino, CNBC, 23 Oct. 2026
  • While that efficacy doesn’t match the performance of a rival drug from Roche, Novartis’ treatment has a cleaner safety profile that could give it a shot at being competitive in the market.
    — Andrew Joseph, STAT, 23 Oct. 2026
Definition of efficacy
Noun
  • Shelie Miller, a University of Michigan professor who studies the environmental impacts of products, said Halloween costumes, like fast fashion, are often made cheaply from plastic materials.
    — Arkansas Online, Arkansas Online, 24 Oct. 2026
  • The cyclists cross the state, generating an economic impact estimated at $25 million.
    — Washington Post, Washington Post, 24 Oct. 2026
Definition of impact
Noun
  • The latter predicts a single universe by denying the universal validity of Schrödinger’s equation.
    — Philipp Strasberg, Scientific American, 20 Oct. 2026
  • According to the court, while NetChoice could challenge the validity of the Georgia law, the group had not sufficiently argued that enforcement of the law would be unconstitutional.
    — Dan Raby, CBS News, 15 Oct. 2026
Definition of validity
Noun
  • These findings point to the importance of substantive local relationships for multinational companies.
    — Margot Edelman, Fortune, 23 Oct. 2026
  • The trade association acknowledged Children’s Mercy’s importance in providing specialized pediatric care, but said ACA coverage must remain financially sustainable across Missouri’s health care system.
    — Kansas City Star, Kansas City Star, 22 Oct. 2026
Definition of importance
Noun
  • The event’s jaw-dropping radiance stunned astronomers, who think that a GRB of this strength strikes Earth only once every 10,000 years.
    — Robin George Andrews, Scientific American, 20 Oct. 2026
  • Most leadership culture pushes people to catalog strengths, build on advantages, project confidence.
    — Flavio Maluf, Forbes.com, 20 Oct. 2026
Definition of strength
Noun
  • The technology’s significance extends beyond completing individual development milestones.
    — Aamir Khollam, Interesting Engineering, 21 Oct. 2026
  • Opel/Stellantis GM walked away from Opel in 2017 and American buyers rarely get a taste of modern Opel products, but the STX has significance for the broader global market.
    — New Atlas, New Atlas, 21 Oct. 2026
Definition of significance
Noun
  • The next president may well also have more power to purchase equity stakes; legislation moving through the Senate would give the Pentagon explicit legal authority to do so.
    — Eleanor Mueller, semafor.com, 22 Oct. 2026
  • Under Ben-Gvir, Israeli police have increasingly allowed Jews to pray at the site, a deliberate provocation to the Arab world, drawing condemnation from Palestinian and Jordanian authorities.
    — Eric Cortellessa, Time, 22 Oct. 2026
Definition of authority

Browse Nearby Words

effectively
effectiveness
effects
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Cite this Entry

“Effectiveness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/effectiveness. Accessed 27 Oct. 2026.

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