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 His company argued in a May lawsuit against licenses issued by the regulator NMDPRA that fuel imports undermine the refinery’s investment and make the domestic market inefficient. — Alexander Onukwue, semafor.com, 18 Sep. 2026 Officials previously said the aging tower had become inefficient and obsolete. — Carole Carlson, Chicago Tribune, 18 Sep. 2026 There are inappropriate procedures and tests, inefficient scheduling, and unused or wasted supplies, to name a few. — Cassandra Thiel, STAT, 8 Sep. 2026 Over the next few seasons, Buium’s higher than optimal, second-contract cap hit will almost surely be inefficient. — Thomas Drance, New York Times, 5 Sep. 2026 See All Example Sentences for inefficient

Recent Examples of Synonyms for inefficient

Adjective

Attempts by The Associated Press to reach the other men or their representatives have been unsuccessful.

— Arkansas Online, Arkansas Online, 2 Oct. 2026
Other searches to find PBHs near and far, however, have so far been unsuccessful.

— Jonathan O'Callaghan, Scientific American, 2 Oct. 2026

Definition of unsuccessful

Adjective

Pike’s unsuccessful appeals have alleged ineffective assistance of counsel and argued that executing her would be unconstitutional because of her mental illness, according to court documents.

— Christina Coulter, PEOPLE, 25 Sep. 2026
After powerful antibiotics proved mostly ineffective, the experts from the aquarium and University of Florida developed a bacteriophage treatment for Jetta, according to a statement sent to Popular Science.

— Margherita Bassi, Popular Science, 24 Sep. 2026

Definition of ineffective

Adjective

Instead of counterproductive regulations, Florida should be lifting rules off.

— Erika Donalds, Sun Sentinel, 23 Sep. 2026
Future work could seek to understand other results, like finding out exactly when this type of interference from above becomes counterproductive, or what the long-term effects of managers taking more of a hands-on role with sales might be.

— Daniel E. Chavez, The Conversation, 22 Sep. 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 4 Oct. 2026.

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Synonyms of inefficient

adjective

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