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
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Recent Examples of effectiveness
While Jaquez did not provide the eye-popping scoring of some of her teammates, the wing brought a cool effectiveness to the defensive side of the ball while tallying a pair of assists and a handful of deflections.
—
Julia Poe, Chicago Tribune, 10 May 2026
The United States and Israel pounded Iran with devastating effectiveness for 37 days, killing much of the country’s leadership and destroying the bulk of its military, yet couldn’t collapse the regime or exact even the smallest concession from it.
—Robert Kagan, The Atlantic, 10 May 2026
Such things are important, as battlefield conditions like fog, rain, smoke, and dust all reduce a laser’s effectiveness in the real world.
—Christopher McFadden, Interesting Engineering, 9 May 2026
The state Office of Cannabis Management, which regulates legal adult-use sales of marijuana, would be the key oversight authority and evaluate the program's effectiveness.
—Caroline Cummings, CBS News, 8 May 2026
Peptides like those in the glow stack are not regulated by the FDA to ensure safety, quality, or effectiveness.
—Jane Yoo, EverydayHealth.com, 8 May 2026
Based on her 30 years of cleaning experience, Hendler recommends following up with a traditional glass cleaner to restore extra shine and remove any visible residue—though this will reduce the effectiveness of the protective coating that dryer sheets can leave behind.
—Jamie Cuccinelli, Martha Stewart, 8 May 2026
Thus, cisplatin is often used in combination with other anticancer agents to limit the development of drug resistance and enhance treatment effectiveness.
—Encyclopedia Britannica, 8 May 2026
Since then, the group has conducted 80 scientifically rigorous clinical trials involving 450,000 participants that have validated the safety and effectiveness of a number of drugs and techniques that are routinely prescribed for patients today.
—Lawrence K. Altman, STAT, 7 May 2026
Julia Poe, Chicago Tribune, 10 May 2026
The United States and Israel pounded Iran with devastating effectiveness for 37 days, killing much of the country’s leadership and destroying the bulk of its military, yet couldn’t collapse the regime or exact even the smallest concession from it.
—Robert Kagan, The Atlantic, 10 May 2026
Such things are important, as battlefield conditions like fog, rain, smoke, and dust all reduce a laser’s effectiveness in the real world.
—Christopher McFadden, Interesting Engineering, 9 May 2026
The state Office of Cannabis Management, which regulates legal adult-use sales of marijuana, would be the key oversight authority and evaluate the program's effectiveness.
—Caroline Cummings, CBS News, 8 May 2026
Peptides like those in the glow stack are not regulated by the FDA to ensure safety, quality, or effectiveness.
—Jane Yoo, EverydayHealth.com, 8 May 2026
Based on her 30 years of cleaning experience, Hendler recommends following up with a traditional glass cleaner to restore extra shine and remove any visible residue—though this will reduce the effectiveness of the protective coating that dryer sheets can leave behind.
—Jamie Cuccinelli, Martha Stewart, 8 May 2026
Thus, cisplatin is often used in combination with other anticancer agents to limit the development of drug resistance and enhance treatment effectiveness.
—Encyclopedia Britannica, 8 May 2026
Since then, the group has conducted 80 scientifically rigorous clinical trials involving 450,000 participants that have validated the safety and effectiveness of a number of drugs and techniques that are routinely prescribed for patients today.
—Lawrence K. Altman, STAT, 7 May 2026
Recent Examples of Synonyms for effectiveness
Noun
-
But his dictionary, with its conclusiveness, was a huge publishing success.—
Louis Menand,
New Yorker,
22 Dec. 2025
Noun
-
For that reason, the study failed to achieve its primary efficacy goal, which was a dose response.—
Adam Feuerstein,
STAT,
14 May 2026
-
Novo has said that the similar efficacy of more than 20% between high-dose Wegovy and Zepbound could help the company win back market share from Lilly.—
Annika Kim Constantino,
CNBC,
12 May 2026
Noun
-
Rowles is also making an impact at Marist in flag football.—
Tony Baranek,
Chicago Tribune,
14 May 2026
-
Not even BriseBois anticipated James, who was signed as a free agent two days into training camp after his draft rights with the Blackhawks expired, would have made such a quick impact.—
Eduardo A. Encina,
The Orlando Sentinel,
13 May 2026
Noun
-
Agent Ammie is the Special Agent, Review Fraud Division, who investigates every single review on Liners to verify its validity and unbiasedness.—
Nia Bowers,
USA Today,
12 May 2026
-
Only a few of the candidates explicitly raise doubts about the validity of the 2020 election on their campaign websites.—
Arkansas Online,
Arkansas Online,
11 May 2026
Noun
-
Palmer’s shot is well blocked by Marc Guehi — which underlines the importance of their decision-making in these moments.—
Cerys Jones,
New York Times,
13 May 2026
-
From 1949 to 1987, the Federal Communications Commission held radio and television stations to a standard requiring them to air opposing sides of public issues of importance, a policy known as the fairness doctrine.—
Encyclopedia Britannica,
Encyclopedia Britannica,
13 May 2026
Noun
-
The bird has long symbolized American values like strength, freedom and independence, said Kochersperger.—
Sarah Raza,
Chicago Tribune,
15 May 2026
-
American oak trees symbolize the enduring strength and resilience of our people and nation.—
Joseph Bonasia,
The Orlando Sentinel,
15 May 2026
Noun
-
That projection is based on the player’s performance in each metric over the last three seasons (five for goalies), weighted for recency where more recent seasons carry more significance and regressed to the mean.—
Dom Luszczyszyn,
New York Times,
17 May 2026
-
The significance of these findings The study suggests human right-handedness may be deeply rooted in the same evolutionary changes that transformed how our ancestors moved and interacted with the world.—
Rupendra Brahambhatt,
Interesting Engineering,
16 May 2026
Noun
-
Chelsea’s squad demographic falls somewhere in between but is probably closer to the former than the latter, and a football legend with his resume should not encounter the authority problems faced by owner BlueCo’s previous hires.—
Liam Twomey,
New York Times,
17 May 2026
-
Health authorities said Congo has stockpiles of Ebola treatments and approximately 2,000 doses of the Ervebo vaccine, though officials cautioned the vaccine is only effective against the Ebola Zaire strain and not against Sudan or Bundibugyo variants.—
Jasmine Baehr,
FOXNews.com,
16 May 2026
Cite this Entry
“Effectiveness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/effectiveness. Accessed 19 May. 2026.
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