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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 However, low-carb diets generally have more evidence supporting their effectiveness in improving blood sugar. — Jillian Kubala, HEALTH, 17 Sep. 2026 Lockheed Martin says the missile offers greater range and effectiveness than existing air-to-air weapons. — Aamir Khollam, Interesting Engineering, 17 Sep. 2026 Yet while this measure is undeniably helpful, its effectiveness may still hinge on strict remarriage qualifications, which may limit the benefits available to deserving families. — Cristina Johnson, Hartford Courant, 16 Sep. 2026 And if defenses begin to pack the box in order to take away Achane’s effectiveness, somebody on the outside will have to make plays. — Miami Herald, 15 Sep. 2026 Yet, negative reviews from Orkin homeowners have to do more with local branches than treatment effectiveness. — Alora Bopray, USA Today, 15 Sep. 2026 In August 2025, Sean Watford, the EPA scientist who created the tool, crafted an assessment of the AI product’s effectiveness. — Story Hinckley, Christian Science Monitor, 15 Sep. 2026 This does not have to mean the beginning of the end for Rodriguez’s effectiveness in 2026. — Kevin Acee, San Diego Union-Tribune, 15 Sep. 2026 However, the lack of compliance with the bill has raised questions about its effectiveness. — Beatrice Nolan, Fortune, 14 Sep. 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
  • The Pentagon has rolled out formal guidance for mandatory testosterone testing for male service members 30 and older, a policy that leaves out women for now and faces questions from medical experts about the need and efficacy of such a program.
    — ABC News, ABC News, 18 Sep. 2026
  • This construct measures four developable capacities—hope, efficacy, resilience and optimism, collectively known as HERO.
    — Expert Panel®, Forbes.com, 18 Sep. 2026
Definition of efficacy
Noun
  • The financial cost is just one measure of the impact of the Iran war, which also is affecting oil prices and the stock market and has led to deaths and injuries of American troops.
    — Ben Finley, Chicago Tribune, 19 Sep. 2026
  • Established in 2006, the Prince Albert II of Monaco Foundation is a non-profit organization that aims to protect the environment and promote sustainable development by limiting climate impacts and promoting renewable energy sources.
    — Julia Teti, Footwear News, 18 Sep. 2026
Definition of impact
Noun
  • Instead, its validity depends on the mathematical rules governing information updates.
    — Rupendra Brahambhatt, Interesting Engineering, 19 Sep. 2026
  • On September 25, the blue state AGs have to respond to a motion from red state Iowa and Montana to take the validity of the antitrust suit to the Supreme Court.
    — Dominic Patten, Deadline, 18 Sep. 2026
Definition of validity
Noun
  • The carrier’s return also highlights the continuing importance of maintenance and modernization in keeping large naval vessels operational decades after their commissioning.
    — Prabhat Ranjan Mishra, Interesting Engineering, 18 Sep. 2026
  • Doing so demonstrates that the company’s leader understands AI’s importance to the bottom line.
    — Andrew Edgecliffe-Johnson, semafor.com, 18 Sep. 2026
Definition of importance
Noun
  • As people age, our muscle mass declines, reducing strength, mobility and balance.
    — Venki Ramakrishnan, Scientific American, 15 Sep. 2026
  • The panel’s findings led to a surge of media interest in the UK and around the world questioning the strength of the prosecution’s case.
    — Billy Stockwell, CNN Money, 15 Sep. 2026
Definition of strength
Noun
  • Prosecutors disputed the significance that the defense placed on the payment, arguing that Noreus agreed to surrender the money only after years of investigation, her indictment and two weeks of trial.
    — Antonio María Delgado, Miami Herald, 16 Sep. 2026
  • Unfortunately, the significance of these exposures usually becomes clearer only years later.
    — Cristina Johnson, Hartford Courant, 16 Sep. 2026
Definition of significance
Noun
  • Belarusian authorities haven't announced any details of the prisoners' release yet.
    — Arkansas Online, Arkansas Online, 17 Sep. 2026
  • European authorities have linked Moscow to a rising number of drone incursions, sabotage incidents, cyberattacks, and other hostile acts across the continent in recent months.
    — Anniek Bao, CNBC, 16 Sep. 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 22 Sep. 2026.

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