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 effectiveness of the approach will depend on how well the systems perform under operational conditions and against evolving electronic warfare threats. — Aamir Khollam, Interesting Engineering, 16 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 Like other supplements, creatine is not FDA-regulated for safety and effectiveness, so the onus is on the consumer to choose a trustworthy brand. — Maggie Ryan, Flow Space, 15 Oct. 2026 The resulting enzymes could be tuned to cut specific proteins in half, and the researchers demonstrated their effectiveness by using them to cut proteins associated with neurological diseases. — ArsTechnica, 14 Oct. 2026 The effectiveness of that design will not be visible in prompt counts or license adoption. — Jason Wojahn, Forbes.com, 13 Oct. 2026 What readers are saying The comments primarily discuss the omission of Moderna's mRNA flu vaccine, mFLUSIVA, from the article, highlighting its recent FDA approval and effectiveness for those over 50. — Kathleen Felton, Washington Post, 10 Oct. 2026 Combining the popular weight-loss medication tirzepatide with another hormone mimic may boost the drug’s effectiveness, according to the results of a recent clinical trial. — Mike McRae 09, New Atlas, 10 Oct. 2026 Increasing the number of personnel in the defense forces does not necessarily increase their effectiveness, Chmut said. — Samya Kullab, Los Angeles Times, 8 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
  • Hope Florida Foundation got a new board and filed tax returns, but criticisms of its efficacy still dog its leaders.
    — Christopher Spata, Miami Herald, 17 Oct. 2026
  • In oncology, where treatment efficacy hinges on precise, patient‑specific data, even a small AI hallucination, such as a mistimed test, can misdirect care.
    — Brad Kreick, Forbes.com, 16 Oct. 2026
Definition of efficacy
Noun
  • Energy-absorbing seats are designed to manage forces transmitted to occupants during an impact, potentially reducing injury risks.
    — Neetika Walter, Interesting Engineering, 17 Oct. 2026
  • Sullivan denied that the law would cut Medicaid for Alaskans, saying the Affordable Care Act had a greater impact and raised insurance premiums in the state drastically.
    — Matthew Choi The Washington Post, Arkansas Online, 17 Oct. 2026
Definition of impact
Noun
  • 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
  • The canvassing board is made up of Garcia and two county judges, and is responsible for determining the validity of ballots and whether they should be counted.
    — Joshua Ceballos, Miami Herald, 2 Oct. 2026
Definition of validity
Noun
  • The princess has also increasingly made the importance of nature a focus of her work, including last year's release of a four-part video series on the power of nature.
    — ABC News, ABC News, 16 Oct. 2026
  • Silver’s comments underscore the importance the league places on obtaining that information.
    — Jessica Golden,Contessa Brewer, CNBC, 16 Oct. 2026
Definition of importance
Noun
  • Battle-tested Like their patron Iran, the Houthis have deployed asymmetric warfare for the 21st century by capitalizing on their strengths — primarily drones and missiles.
    — NBC news, NBC news, 13 Oct. 2026
  • Treatments for acne range from over-the-counter creams and lotions to prescription-strength medications.
    — Adithi Ramakrishnan, Los Angeles Times, 13 Oct. 2026
Definition of strength
Noun
  • Bears Ears is a living cultural landscape and sacred ancestral homeland of deep significance to Tribal Nations.
    — Mary Beth Laughton, Time, 14 Oct. 2026
  • Hassen discussed the significance of Type V composite pressure vessels, and their potential.
    — Georgina Jedikovska, Interesting Engineering, 14 Oct. 2026
Definition of significance
Noun
  • In the narrative to has unfolded from authorities and passenger accounts, Machchhar had the presence of mind to open the locked door of the cockpit after he was stabbed.
    — Cynthia Littleton, Variety, 15 Oct. 2026
  • Jackson has not been identified by authorities as a suspect or person of the interest in the killing.
    — Nancy Dillon, Rolling Stone, 15 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 20 Oct. 2026.

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