deficient

adjective

di-ˈfi-shənt How to pronounce deficient (audio)
Definition of deficientnext
1
as in incomplete
lacking some necessary part a diet deficient in calcium can lead to weak bones

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2
as in unacceptable
falling short of a standard woefully deficient eyesight kept him out of military service

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Antonyms & Near Antonyms
3
as in lacking
not coming up to an expected measure or meeting a particular need too deficient in common sense to be trusted to stay by himself

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Antonyms & Near Antonyms

Example Sentences

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 deficient The American Urological Association says that a total testosterone level below 300 ng/dL, when combined with symptoms of low testosterone, should be considered deficient. — Melissa Rudy, FOXNews.com, 20 July 2026 The Supreme Judicial Court later concluded that the Attorney General’s summary was legally deficient because of the language her office inserted — and removed the question from the ballot. — Robert Cordy, Boston Herald, 19 July 2026 The same logic would apply to a service member who is truly hormone deficient — replacement therapy could help. — Dr. Jamin Brahmbhatt, CNN Money, 16 July 2026 First-year students, according to thousands of professors, are arriving severely deficient in math and weak in writing skills. — Jaweed Kaleem, Los Angeles Times, 14 July 2026 See All Example Sentences for deficient
Recent Examples of Synonyms for deficient
  1. incomplete
  2. unacceptable
  3. lacking
  4. wrong
  5. inadequate
  6. poor
  7. insufficient
  8. lame
Adjective
  • Twice in 2024, the city determined the application was incomplete.
    — George Avalos, Mercury News, 5 Aug. 2026
  • Reddington attempted to cast doubt on Brower's testimony by arguing that the level of drugs in Clancy's system provided an incomplete view of her overall health.
    — Peter Charalambous, ABC News, 5 Aug. 2026
Definition of incomplete
Adjective
  • The plan is to then gradually introduce louder sounds, Coen added, to discover the level at which a sonic boom noise goes from being acceptable to unacceptable.
    — Jacopo Prisco, CNN Money, 6 Aug. 2026
  • Given the national security stakes, the prospect of foreign governments being able to suspend access to critical models at a whim started to feel like an unacceptable risk.
    — Beatrice Nolan, Fortune, 5 Aug. 2026
Definition of unacceptable
Adjective
  • So a resistance surveillance network across places where this is lacking, such as northwestern Nigeria, would bring a huge return on investment.
    — Christine Ro, Forbes.com, 23 July 2026
  • Despite severely lacking resources, the monuments men and women were able to find and retrieve more than five million items, many of them artworks that had been stolen by the Axis forces.
    — Encyclopedia Britannica, Encyclopedia Britannica, 14 July 2026
Definition of lacking
Adjective
  • Seneca, the Roman philosopher, argued that people kept getting the message of Homer’s epic poems wrong.
    — John Blake, CNN Money, 2 Aug. 2026
  • One person was killed and two others were critically injured when a wrong-way driver crashed into several other vehicles on Friday evening on the Dan Ryan Expressway on the South Side of Chicago.
    — Todd Feurer, CBS News, 1 Aug. 2026
Definition of wrong
Adjective
  • In the eyes of many groups who provide assistance to the city’s homeless residents, Atlanta’s response to the broiling temperatures was woefully inadequate.
    — Drew Kann, AJC.com, 4 Aug. 2026
  • In a statement describing Abbott’s pause as inadequate, Hinojosa called for Abbott to issue a full moratorium on data center development until the state legislature can pass stricter rules.
    — Jeremy Hsu, ArsTechnica, 4 Aug. 2026
Definition of inadequate
Adjective
  • Covid-19 wasn’t immediately recognized as a disease with airborne transmission with the potential to spread beyond the 6-foot social distancing measure, especially in places with poor ventilation or around activities with heavy breathing.
    — Deidre McPhillips, CNN Money, 4 Aug. 2026
  • Crepe myrtles may not bloom due to poor pruning, low light, watering issues, weak soil, or pests.
    — Lauren Landers, The Spruce, 4 Aug. 2026
Definition of poor
Adjective
  • Accelerating vaccine production is necessary but insufficient to counter a future pandemic.
    — Arthur L. Kellermann, Forbes.com, 6 Aug. 2026
  • Testing the soil before providing irrigation will prevent you from overwatering or underwatering your boxwoods and help alleviate browning caused by insufficient or excessive soil moisture.
    — Samantha Johnson, Martha Stewart, 5 Aug. 2026
Definition of insufficient
Adjective
  • The jokes are still wildly scattershot and frequently, knowingly lame; the production is still cheap and cheerfully scrappy; the whole ragged enterprise is still reliant on the evident affection and chemistry between its players to hold it together.
    — Guy Lodge, Variety, 5 Aug. 2026
  • A couple solid set-pieces, a lame evil corporate villain, a limp Act 1 origin story, and the perfect scene where Pepper performs open-heart surgery on Tony complete the picture.
    — EW Staff, Entertainment Weekly, 3 Aug. 2026
Definition of lame

Browse Nearby Words

deficiency
deficient
deficiently
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Cite this Entry

“Deficient.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/deficient. Accessed 7 Aug. 2026.

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Nglish: Translation of deficient for Spanish Speakers

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