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

Other Words from deficient

Adjective

deficiently adverb

Synonyms & Antonyms for deficient

Synonyms: Adjective

Antonyms: Adjective

Visit the Thesaurus for More 

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 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 Recent Examples on the Web: 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

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.

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

Learn More About deficient

Time Traveler for deficient

Time Traveler

The first known use of deficient was in 1581

See more words from the same year

Dictionary Entries Near deficient

deficiency disease

deficient

deficient number

See More Nearby Entries 

Statistics for deficient

Last Updated

11 Aug 2022

Cite this Entry

“Deficient.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deficient. Accessed 19 Aug. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

More Definitions for deficient

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

More from Merriam-Webster on deficient

Nglish: Translation of deficient for Spanish Speakers

Britannica English: Translation of deficient for Arabic Speakers

WORD OF THE DAY

Test Your Vocabulary

Commonly Confused Words Quiz

  • vector image of a face with thought expression
  • I went to the ______ store to buy a birthday card.
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Universal Daily Crossword

A daily challenge for crossword fanatics.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!