effectiveness

American  

[ih-fek-tiv-nis, ee-fek‐] / ɪˈfɛk tɪv nɪs, iˈfɛk‐ /

Rarely effectivity

noun

1. the quality of producing an intended or desired result.

   For maximum effectiveness of your weight loss plan, you need to combine exercise with a healthy diet.

2. the quality of producing a deep or vivid impression.

   We were struck by the evident appeal and effectiveness of these short, dramatic, upbeat video stories.

3. a measure of the success of a vaccine or other pharmaceutical when used in the real world, as opposed to the controlled environment of a clinical trial.

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Other Word Forms

• subeffectiveness noun
• supereffectiveness noun
• uneffectiveness noun

Etymology

Origin of effectiveness

First recorded in 1600–10; effective ( def. ) + -ness ( def. )

Example Sentences

He said this new information, which will likely remove the recycling label from the cartons, also underscores the effectiveness of the law.

From Los Angeles Times

However, the intended effectiveness of the flu vaccine against symptomatic disease caused by the new subvariant remains uncertain, the World Health Organization said.

From Los Angeles Times

To further investigate the drug's potential in treating Alzheimer's disease, the team wanted to evaluate its effectiveness at halting the earliest damage.

From Science Daily

Additional toxicological testing, human clinical trials, and standardized preparation methods are still required to confirm safety, effectiveness, and quality.

From Science Daily

He tells us: "Today there is no independent evidence at scale for the effectiveness of these tools in education, or for their safety, or even for the idea they have a positive impact."

From BBC

Related Words

• capability
• efficacy
• efficiency
• potency
• power
• success