Definitions

deficient

[dih-fish-uhnt] / dɪˈfɪʃ ənt /

ADJECTIVE

imperfect, inadequate

Synonyms

STRONGEST

defective faulty flawed impaired incomplete inferior insufficient lacking scarce skimpy unsatisfactory weak

WEAK

amiss bad damaged exiguous found wanting infrequent injured marred meager not cut out for not enough not make it not up to scratch outta gas rare scant scanty second fiddle second string short shy sketchy third-string unassembled unequal unfinished wanting

Antonyms

STRONGEST

abundant adequate enough perfect strong sufficient

WEAK

ample excessive faultless flawless satisfactory superfluous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The vitamin D deficient group also required more opioid medication.

From Science Daily • May 20, 2026

The county conducted an audit of Harm Reduction-SD in April 2023 that revealed “significant financial control weaknesses including insufficient bank reconciliations and a deficient general ledger,” prosecutors allege.

From Los Angeles Times • Feb. 19, 2026

"If it turns out the shipowners were deficient, they will expect the full force of the law," Lopez told reporters.

From Barron's • Jan. 27, 2026

After MI5 apologised, we then showed that inquiries into what happened by MI5 and the government were deficient and unreliable, with further falsehoods provided to the court.

From BBC • Jan. 25, 2026

But I do know we’re deficient in some way.

From "Tuesdays with Morrie" by Mitch Albom

Vocabulary lists containing deficient

Tuesdays with Morrie

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Oh, No! Synonyms for "Bad"

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50 Words from Jane Austen's "Pride & Prejudice"

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