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

I write here, understand, as a deficient moralist.

From The Wall Street Journal • Apr. 3, 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

Deere leverages AI to help farmers cut costs—by reducing labor required to operate equipment, minimizing wasted crop chemicals, and applying fertilizer more precisely where soil nutrients are deficient.

From Barron's • Feb. 2, 2026

Jutta clutches her bag between her knees; she is certain that he was wounded in the war, that he will try to start a conversation, that her deficient French will betray her.

From "All the Light We Cannot See" by Anthony Doerr

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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