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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Antonyms & Near Antonyms
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 What is often misunderstood is that any of these virtuous behaviors can manifest as deficient vices when underdeveloped and as excess vices when strong but unsupported by the other 10 character dimensions, as evidenced by Steve Jobs. — Mary Crossan, Forbes.com, 23 June 2026 Nemec has great mobility and skills at both ends of the ice with an emphasis on offense, checking off a ton of boxes for an offense-deficient Flames team. — Peter Baugh, New York Times, 23 June 2026 About 220,000 need major repair or replacement, and 41,677 are rated poor, also called structurally deficient. — Alex Krasnok, Fortune, 21 June 2026 About 220,000 need major repair or replacement, and 41,677 are rated poor, also called structurally deficient. — Alex Krasnok, The Conversation, 19 June 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
  • Dmitri published his father’s incomplete novel, The Original of Laura, in 2009, going against his father’s wishes.
    — Carly Tagen-Dye, PEOPLE, 15 July 2026
  • Second, a burger without fries is incomplete, and the quality of fries matters.
    — Sean Timberlake, Sacbee.com, 15 July 2026
Definition of incomplete
Adjective
  • Critics say such plans are wholly unacceptable because light pollution from so many large, bright satellites would radically degrade views of the night sky.
    — Mary Randolph, Scientific American, 16 July 2026
  • For the union, this is unacceptable and yet another issue their members are facing.
    — Carmela Karcher, CBS News, 14 July 2026
Definition of unacceptable
Adjective
  • 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
  • Furthermore, beware of any ancestral diet that is completely lacking in particular nutrients and the foods that bring them such as grains that bring fiber and different vitamins and minerals.
    — Bruce Y. Lee, Forbes.com, 10 July 2026
Definition of lacking
Adjective
  • Under rules brought in for the World Cup, the reviewable decisions and incidents now include mistaken identity when the referee shows a yellow or red card but clearly penalises the wrong player of either team.
    — Stuart James, New York Times, 12 July 2026
  • Even when Romanzy goes off on how stupid and ugly Caleb is — and gossips that his parents abandoned him because something must be wrong with him — Mary goes along with it.
    — Maggie Fremont, Vulture, 11 July 2026
Definition of wrong
Adjective
  • Boating accidents are a regular occurrence in the Southeast Asian nation, where extreme weather, frequent flooding and inadequate maintenance have led to tragedies.
    — CBS News, CBS News, 13 July 2026
  • Experts say the high death toll may reflect factors common to past entertainment venue fires, including inadequate safety measures.
    — ABC News, ABC News, 13 July 2026
Definition of inadequate
Adjective
  • Prolonged exposure to heat can lead to insufficient or poor sleep, compromising the immune system, increasing the risk for cardiovascular disease and diminishing cognitive performance.
    — Adriana Pérez, Chicago Tribune, 13 July 2026
  • On top of this, subterranean drip systems often clog with mineral deposits, sediment, and algae, which Nad warns may eventually require repairs or replacement of portions of the system, particularly in areas with hard water or poor filtration.
    — Kamron Sanders, The Spruce, 13 July 2026
Definition of poor
Adjective
  • Conversely, there are moments throughout Pompeii where the trail goes cold due to insufficient documentation from 2,000 years ago, frustrating Hiddleston in the process.
    — Brian Davids, HollywoodReporter, 16 July 2026
  • When controlling for traditional predictors of mortality, only smoking showed a stronger association with life expectancy than insufficient sleep.
    — Samantha Agate, Miami Herald, 15 July 2026
Definition of insufficient
Adjective
  • But instead of playing kingmaker, the lame-duck governor has refused to get behind a candidate to succeed him.
    — Romy Ellenbogen Herald, Miami Herald, 6 July 2026
  • Stronger and more flavorful than in your original lame iteration?
    — Padgett Powell, Harpers Magazine, 30 June 2026
Definition of lame

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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 18 Jul. 2026.

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