deficient

adjective
de·​fi·​cient | \ di-ˈfi-shənt How to pronounce deficient (audio) \

Definition of deficient

 (Entry 1 of 2)

1 : lacking in some necessary quality or element deficient in judgment bones deficient in calcium
2 : not up to a normal standard or complement (see complement entry 1 sense 1b(1)) : defective deficient strength … rusted and aging pipes … abetted by deficient maintenance and sabotage.— Adam Nossiter

deficient

noun

Definition of deficient (Entry 2 of 2)

: a person or thing that is deficient a mental deficient

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Other Words from deficient

Adjective

deficiently adverb

Synonyms & Antonyms for deficient

Synonyms: Adjective

fragmental, fragmentary, half, halfway, incomplete, partial

Antonyms: Adjective

complete, entire, full, intact, integral, perfect, whole

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Examples of deficient in a Sentence

Adjective

Several bridges in the city are structurally deficient. a diet deficient in calcium can lead to weak bones

Recent Examples on the Web: Adjective

Supplements from the Supermarket Vitamin D: This vitamin is imperative to keeping your immune system strong, and most of us are vitamin D deficient. Aarti Sanan, Redbook, "Wedding Dress Challenge: Clean, Green, Juicing Machine," 20 Apr. 2012 The viaduct is considered functionally obsolete and structurally deficient. David Porter, Fox News, "NYC commuters are spared a nightmare as road project starts," 21 Aug. 2018 Amazon has upgraded the sound quality on all of its new Echo devices coming out this year, but the improvements are most noticeable on the Dot simply because of how deficient the prior model was. Dan Seifert, The Verge, "Amazon Echo Dot (3rd gen) review: better looks, better sound, same price," 12 Oct. 2018 The viaduct is considered functionally obsolete and structurally deficient. David Porter, Fox News, "NYC commuters are spared a nightmare as road project starts," 21 Aug. 2018 The viaduct is considered functionally obsolete and structurally deficient. David Porter, The Seattle Times, "NYC commuters are spared a nightmare as road project starts," 20 Aug. 2018 Bridges can be both functionally obsolete and structurally deficient. Erik Sofge, Popular Mechanics, "Just How Fragile Are America's Bridges?," 28 May 2013 The dangers of losing oxygen, explained The US Occupational Safety and Health Administration considers environments with less than a 19.5 percent oxygen by volume to be oxygen-deficient, and a health hazard. Brian Resnick, Vox, "Why the trapped Thai soccer team is in increasing trouble: they’re running out of oxygen," 6 July 2018 Fish is the only good dietary sources of vitamin D. Fatty fish is an excellent source of vitamin D, and important nutrient that over 40% of people may be deficient in. Orthocincy, Cincinnati.com, "Benefits of eating fish," 19 June 2018

Recent Examples on the Web: Noun

But rising home prices are bailing out large numbers of the equity deficient: their number is down by more than 1.2 million in the last 12 months. Kenneth R. Harney, miamiherald, "Which U.S. neighborhood has homeowners with the most equity? Answer may surprise you," 22 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'deficient.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of deficient

Adjective

1581, in the meaning defined at sense 1

Noun

1906, in the meaning defined above

History and Etymology for deficient

Adjective

borrowed from Latin dēficient-, dēficiens, present participle of dēficere "to leave without enough, let down, be lacking, run short, fail," from dē- de- + facere "to make, bring about, perform, do" — more at fact

Noun

derivative of deficient entry 1

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Statistics for deficient

Last Updated

16 Mar 2019

Look-up Popularity

Time Traveler for deficient

The first known use of deficient was in 1581

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More Definitions for deficient

deficient

adjective

English Language Learners Definition of deficient

: not having enough of something that is important or necessary
: not good enough : not as good as others

deficient

adjective
de·​fi·​cient | \ di-ˈfi-shənt How to pronounce deficient (audio) \

Kids Definition of deficient

: lacking something necessary for completeness or health Her diet is deficient in proteins.

deficient

adjective
de·​fi·​cient | \ di-ˈfish-ənt How to pronounce deficient (audio) \

Medical Definition of deficient

 (Entry 1 of 2)

1 : lacking in some necessary quality or element a deficient diet
2 : not up to a normal standard or complement deficient strength
3 : having, relating to, or characterized by a genetic deletion

deficient

noun

Medical Definition of deficient (Entry 2 of 2)

: one that is deficient a mental deficient

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Comments on deficient

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