deficient
1 of 2adjective
de·fi·cient di-ˈfi-shənt 
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
Adam Nossiter deficiently adverb
deficient
2 of 2noun
: a person or thing that is deficient
a mental deficient
Synonyms
Adjective
- fragmental
- fragmentary
- half
- halfway
- incomplete
- partial
See all Synonyms & Antonyms 
Example Sentences
Adjective Several bridges in the city are structurally deficient. a diet deficient in calcium can lead to weak bones
Recent Examples on the Web Rachel Nuwer, Scientific American, 4 Aug. 2022 The monitor supplemented my port-deficient Dell XPS 13 laptop quite well. Scharon Harding, Ars Technica, 10 June 2022 All 12 participants had similar mutations in what’s called mismatch repair-deficient colorectal cancer, which occurs in about 5 to 10 percent of colorectal cancers, per the study. Margaret Osborne, Smithsonian Magazine, 8 June 2022 Is BlackRock’s $10 trillion in assets enough to engineer a self-fulfilling prophecy of a premature leap to a carbon-free but energy-deficient future? WSJ, 2 June 2022 Machines are great for transactional purposes but are deficient in relational connection. Expert Panel®, Forbes, 30 June 2022 Fifteen percent of the population are deficient in vitamin B12, for example, particularly those who practice a vegan or vegetarian diet. Dr. Michael Daignault, USA TODAY, 30 June 2022 Nearly half of Americans are deficient in the mineral, which can help ease stress and relax the body—among other benefits. Ali Francis, Bon Appétit, 21 June 2022 The Netherlands is famously deficient in something bulbs need: land. John Kelly, Washington Post, 28 June 2022 Valerie Pavilonis, USA TODAY, 9 Feb. 2022 The best way to hide the deficient, though, is through a dominating offense which brings us back to Jackson and Roman. Mike Preston, baltimoresun.com, 5 June 2021 Some research is also starting to show that many severe COVID-19 patients are vitamin D deficient. Fedor Kossakovski, Science, 15 Dec. 2020 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, 22 Aug. 2017 See More
Adjective
The model projected that more than half of the data-deficient species included in the analysis are threatened with extinction. Rachel Nuwer, Scientific American, 4 Aug. 2022 The monitor supplemented my port-deficient Dell XPS 13 laptop quite well. Scharon Harding, Ars Technica, 10 June 2022 All 12 participants had similar mutations in what’s called mismatch repair-deficient colorectal cancer, which occurs in about 5 to 10 percent of colorectal cancers, per the study. Margaret Osborne, Smithsonian Magazine, 8 June 2022 Is BlackRock’s $10 trillion in assets enough to engineer a self-fulfilling prophecy of a premature leap to a carbon-free but energy-deficient future? WSJ, 2 June 2022 Machines are great for transactional purposes but are deficient in relational connection. Expert Panel®, Forbes, 30 June 2022 Fifteen percent of the population are deficient in vitamin B12, for example, particularly those who practice a vegan or vegetarian diet. Dr. Michael Daignault, USA TODAY, 30 June 2022 Nearly half of Americans are deficient in the mineral, which can help ease stress and relax the body—among other benefits. Ali Francis, Bon Appétit, 21 June 2022 The Netherlands is famously deficient in something bulbs need: land. John Kelly, Washington Post, 28 June 2022 Noun
According to a 2010 article from the International Journal of Health Sciences, over 1 billion people worldwide are vitamin D deficient. Valerie Pavilonis, USA TODAY, 9 Feb. 2022 The best way to hide the deficient, though, is through a dominating offense which brings us back to Jackson and Roman. Mike Preston, baltimoresun.com, 5 June 2021 Some research is also starting to show that many severe COVID-19 patients are vitamin D deficient. Fedor Kossakovski, Science, 15 Dec. 2020 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, 22 Aug. 2017 See More Word History
Etymology
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
First Known Use
Adjective
1581, in the meaning defined at sense 1
Noun
1906, in the meaning defined above
Kids Definition
deficient
adjective
de·fi·cient di-ˈfi-shənt
: lacking something necessary for completeness or health
Her diet is deficient in proteins.
Medical Definition
deficient 1 of 2
adjective
de·fi·cient di-ˈfish-ənt
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
2 of 2noun
: one that is deficient
a mental deficient
deficient
adjective
1
as in incomplete
lacking some necessary part a diet deficient in calcium can lead to weak bones Synonyms & Similar Words
Relevance
- incomplete
- flawed
- damaged
- partial
- half
- fragmentary
- unfinished
- imperfect
- fragmental
- impaired
- halfway
- injured
- spoiled
- broken
- marred
- sketchy
- uncompleted
- unassembled
Antonyms & Near Antonyms
- perfect
- complete
- integral
- whole
- intact
- full
- entire
- unimpaired
- flawless
- undamaged
- unbroken
- uninjured
- finished
- unmarred
- completed
2
as in unacceptable
falling short of a standard woefully deficient eyesight kept him out of military service Synonyms & Similar Words
- unacceptable
- wrong
- poor
- lame
- flawed
- bad
- lacking
- unsatisfactory
- substandard
- inadequate
- pathetic
- awful
- terrible
- defective
- inferior
- suboptimal
- horrible
- disastrous
- subpar
- wretched
- insufficient
- ill
- crummy
- brutal
- dreadful
- dissatisfactory
- lousy
- sour
- from hunger
- bastard
- off
- below par
- wanting
- paltry
- wack
- useless
- bush
- faulty
- rotten
- worthless
- under par
- punk
- abysmal
- gross
- crumby
- short
- miserable
- atrocious
- lesser
- deplorable
- common
- bush-league
- shoddy
- detestable
- damnable
- egregious
- mediocre
- vile
- abominable
- stinky
- valueless
- execrable
- horrendous
- unspeakable
- scanty
- flagrant
- gnarly
- reprehensible
- crappy
- junky
- meager
- sucky
- bitchin'
- odious
- coarse
- skimpy
- miserly
- shabby
- trashy
- stingy
- bum
- cheesy
- rubbishy
- mean
- skimp
- sleazy
- low-grade
- spare
- villainous
- second-rate
- niggardly
- counterfeit
- scurrilous
- meagre
- low-rent
- sham
- miscreant
- fake
- phony
- cut-rate
- phoney
Antonyms & Near Antonyms
- adequate
- satisfactory
- acceptable
- standard
- fine
- decent
- tolerable
- okay
- passable
- superior
- sufficient
- respectable
- excellent
- classical
- better
- perfect
- great
- divine
- exceptional
- classic
- splendid
- superb
- superlative
- prime
- special
- par excellence
- wonderful
- noble
- marvellous
- mean
- terrific
- marvelous
- stellar
- exceptional
- heavenly
- neat
- top
- premium
- sensational
- keen
- average
- unsurpassed
- fabulous
- grand
- dandy
- capital
- choice
- swell
- minimal
- suitable
- borderline
- all right
- slick
- useful
- mediocre
- fancy
- sterling
- supernal
- nifty
- worthy
- fair
- unexceptional
- middling
- banner
- OK
- boss
- first-rate
- groovy
- top-notch
- crackerjack
- high-test
- first-class
- tip-top
- bang-up
- satisfying
- high-grade
- gratifying
- A1
- jim-dandy
- so-so
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 Synonyms & Similar Words
- lacking
- inadequate
- insufficient
- scarce
- low
- short
- unsatisfactory
- unacceptable
- substandard
- wanting
- shy
- sparse
- poor
- scanty
- meager
- skimpy
- lean
- stingy
- scant
- light
- slender
- mere
- minimum
- spare
- niggardly
- small
- meagre
- slim
- skimp
- bare
- slight
- hand-to-mouth
Antonyms & Near Antonyms
- adequate
- sufficient
- enough
- abundant
- plentiful
- ample
- copious
- generous
- liberal
- bountiful
- bounteous
- supplemented
- plenteous
- enlarged
- satisfactory
- overflowing
- expanded
- tolerable
- teeming
- plenitudinous
- rich
- large
- substantial
- considerable
- lavish
- super
- oversized
- luxuriant
- abounding
- sizeable
- sizable
- oversize
- big
- hefty
- jumbo
- largish
- king-sized
- king-size