INEFFICIENT Synonyms: 35 Similar and Opposite Words

inefficient

adjective

ˌi-nə-ˈfi-shənt

Definition of inefficient

as in unsuccessful

not producing the desired result inefficient measures to solve the problem of teenage smoking

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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 inefficient On the other hand, detailed reviews of individual high-cost claims frequently reveal inefficient areas in an employer’s health plan. — Bruce Roffe, Forbes.com, 12 Aug. 2026 Earlier research had shown that unclonable encryption was possible, but existing approaches were either inefficient or needed certain assumptions to be secure. — Peter Hall, Scientific American, 31 July 2026 Thanks to a shortage of memory chips produced by the profoundly resource-hungry and inefficient AI industry, consumer electronics are becoming much more expensive across the board. — Damon Beres, The Atlantic, 29 July 2026 Nearly all of Las Vegas' indoor water use is recycled, meaning the issues of conservation now lie with outdoor watering and inefficient cooling systems. — Carly Sauvageau, USA Today, 28 July 2026 See All Example Sentences for inefficient

Recent Examples of Synonyms for inefficient

Adjective

Steyer, a Democratic billionaire who spent more than $215 million of his own money in his unsuccessful bid for governor, took fire from rivals for paying content creators.

— Sophie Austin, Fortune, 8 Aug. 2026
Multiple attempts by Star reporters to contact McGee Thursday afternoon were unsuccessful.

— Ilana Arougheti Updated August 7, Kansas City Star, 7 Aug. 2026

Definition of unsuccessful

Adjective

Dawicki hopes the test will reduce the unnecessary use of antibiotics, and slow the current march toward antibiotic resistance that has already rendered several antibiotics ineffective.

— Alice Park, Time, 7 Aug. 2026
But the difference isn't so stark as to render CDs ineffective now.

— Matt Richardson, CBS News, 6 Aug. 2026

Definition of ineffective

Adjective

But worse, military action in Mexico would ultimately be counterproductive in the fight against drug cartels.

— Chris Shays, Hartford Courant, 7 Aug. 2026
Ultimately, glorifying sleep deprivation is counterproductive; prioritizing sleep is key for career longevity and productivity, while chronic insomnia leads to impaired judgment and hinders professional growth.

— Mena Mirhom, Forbes.com, 1 Aug. 2026

Definition of counterproductive

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inefficiency

inefficient

inefficiently

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“Inefficient.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficient. Accessed 17 Aug. 2026.

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Synonyms of inefficient

adjective

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