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 Calcium and vitamin D are often supplemented together for bone health, but research shows mixed results on their effectiveness in improving bone mineral density or reducing fracture risk. — Jennifer Lefton, Verywell Health, 3 Sep. 2026 Milwaukee police officials have stood by the technology's effectiveness, despite months of criticism and two officers facing criminal charges for misuse of the system. — David Clarey, jsonline.com, 3 Sep. 2026 A lot of the show’s effectiveness had to do with viewers eager to play along. — Emily Nussbaum, New Yorker, 3 Sep. 2026 Monitoring is essential for evaluating contamination and the effectiveness of remediation efforts. — Encyclopedia Britannica, 3 Sep. 2026 In August, Novo launched a study on effectiveness and safety of lower maintenance doses of the Wegovy pill, but the study could take months, even years, to complete. — Ken Alltucker, USA Today, 2 Sep. 2026 Product margins are also ignored when evaluating campaign effectiveness. — John Readman, Forbes.com, 1 Sep. 2026 Heading into September, Counsell’s late-inning options include de facto closer Jacob Webb, returning closer Daniel Palencia and a mystery man that could depend on Edward Cabrera’s health and effectiveness. — Paul Sullivan, Chicago Tribune, 31 Aug. 2026 Jia said there are challenges ahead for developing an ethical framework for AI chatbots, which include issues related to privacy, safety and lack of long-term evidence on the effectiveness of the new technology. — Livi Stanford, Hartford Courant, 31 Aug. 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 protein building blocks can have anti-inflammatory and muscle-building properties – though studies and safety analyses of their benefits and efficacy as supplements or injections vary widely.
    — Cara Kelly, USA Today, 30 Aug. 2026
  • These second-generation antihistamines have similar efficacy, fewer undesirable side effects, and far less potential for abuse, according to the FDA.
    — Dr. Jill Grimes, CNN Money, 29 Aug. 2026
Definition of efficacy
Noun
  • Freshman wide receiver Jonathon Lee is making an immediate impact on the program.
    — Michael Osipoff, Chicago Tribune, 29 Aug. 2026
  • Therefore, analysts note that if extreme weather worsens water and power scarcity, the impact could ripple through the entire semiconductor supply chain.
    — , CNBC, 28 Aug. 2026
Definition of impact
Noun
  • Hudak indicated in Friday’s news conference that police are looking into the validity of the document.
    — Michelle Marchante, Miami Herald, 28 Aug. 2026
  • And as with the actual Stanford prison experiment, questions of ethics and scientific validity are sidelined in favor of getting splashy results by any means necessary.
    — Angie Han, HollywoodReporter, 27 Aug. 2026
Definition of validity
Noun
  • Thanks to my friends’ beloved babies and the perks of my job—which have included putting together a list of essential children’s books—I’ve been thinking a lot about the importance of reading with children.
    — Emma Sarappo, The Atlantic, 28 Aug. 2026
  • Fame was of prime importance to the ancient Greeks, and Wilson is the rare classical scholar who has firsthand knowledge of a public life.
    — ABC News, ABC News, 28 Aug. 2026
Definition of importance
Noun
  • But the country's key stock benchmarks are struggling to reflect that strength, hinting at a festering disconnect between markets and the economy.
    — Priyanka Salve, CNBC, 3 Sep. 2026
  • She was invested in young women and keeping the door open for the next generation of leaders, and her advocacy was always about fighting for the strength, intelligence, and dignity of women everywhere.
    — Noe Padilla, USA Today, 3 Sep. 2026
Definition of strength
Noun
  • The first prince of Norwegian descent born in 567 years, his birth held special significance for the young Norwegian monarchy.
    — Stefania Conrieri, Vanity Fair, 28 Aug. 2026
  • Two days later, then-Defense Secretary Lloyd Austin canceled them, saying a decision of such significance should rest with him.
    — Kaelan Deese, The Washington Examiner, 27 Aug. 2026
Definition of significance
Noun
  • Local authorities say rules have been set by US authorities barring personnel from visiting cannabis dispensaries and taking part in watersports including jet skiing and parasailing.
    — Brad Lendon, CNN Money, 2 Sep. 2026
  • Interior Minister Alexander Dobrindt said forensic evidence and intelligence findings tied Russia to the attack, in which authorities found a drone carrying an explosive device beside a Ukrainian Antonov cargo aircraft at Leipzig/Halle Airport.
    — Brittany Miller, FOXNews.com, 2 Sep. 2026
Definition of authority

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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 4 Sep. 2026.

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