deficiency

noun

de·​fi·​cien·​cy di-ˈfi-shən-sē How to pronounce deficiency (audio)
plural deficiencies
Synonyms of deficiency
1
: the quality or state of being defective or of lacking some necessary quality or element : the quality or state of being deficient : inadequacy
suffers from a deficiency of critical thinking
2
: an amount that is lacking or inadequate : shortage
staffing deficiencies
: such as
a
: a shortage of substances necessary to health
a vitamin C deficiency
hormone deficiencies
b
genetics : deletion sense 2b(1)

Synonyms of deficiency

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Examples of deficiency in a Sentence

The disease may be caused by nutritional deficiencies. The book's major deficiency is its poor plot. a deficiency of vitamin C There are several deficiencies in his plan. The accident was caused by deficiencies in the engine.
Recent Examples on the Web
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.
An independent committee found that the Housing Bureau's independent checking unit, the Buildings Department, the Fire Services Department and the Labor Department had deficiencies in their supervision work, Lee said. — Arkansas Online, 30 Oct. 2026 Heavy menstrual bleeding can lead to iron deficiency, and that can actually impair a girl’s ability to participate in activity or exercise, and also can impair cardiovascular health. — Elizabeth Cooney, STAT, 26 Oct. 2026 The coaster’s most recent inspection, on March 16, reported no violations, deficiencies, citations or red tags, according to King. — Alaa Elassar, CNN Money, 24 Oct. 2026 Experts believe estrogen deficiency may play a direct role, but most studies that have looked at whether taking hormone therapy can reduce the risk have been small and inconclusive (though research in this area is ongoing). — Cheyenne Buckingham, Washington Post, 24 Oct. 2026 See All Example Sentences for deficiency

Word History

Etymology

defici(ent) entry 1 + -ency

First Known Use

1603, in the meaning defined at sense 1

Time Traveler
The first known use of deficiency was in 1603

Phrases Containing deficiency

Rhymes for deficiency

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Browse Nearby Words

deficience
deficiency
deficiency account
See all Nearby Words

Cite this Entry

“Deficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deficiency. Accessed 31 Oct. 2026.

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Kids Definition

deficiency

noun
de·​fi·​cien·​cy di-ˈfish-ən-sē How to pronounce deficiency (audio)
plural deficiencies
1
: the quality or state of being deficient
2
: the quality or state of being inadequate
especially : a shortage of substances necessary to health

Medical Definition

deficiency

noun
de·​fi·​cien·​cy di-ˈfish-ən-sē How to pronounce deficiency (audio)
plural deficiencies
1
: a shortage of substances (as vitamins) necessary to health
2
: deletion

Legal Definition

deficiency

noun
de·​fi·​cien·​cy di-ˈfi-shən-sē How to pronounce deficiency (audio)
plural deficiencies
: an amount that is lacking or inadequate: as
a
: the difference between the amount of tax owed and the amount of tax paid
b
: the difference between the amount owed under a security agreement and the amount the creditor is able to recover upon default of the debtor by selling the collateral
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