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.

A panel of medical experts, asked by prosecutors to investigate Maradona's medical team, said the treatment he received at his home was "deficient and reckless".

From BBC • Apr. 14, 2026

I write here, understand, as a deficient moralist.

From The Wall Street Journal • Apr. 3, 2026

These provide calories but lack the sterols bees need, leaving colonies nutritionally deficient.

From Science Daily • Mar. 27, 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

On bad days it was a reminder of all the ways I am deficient.

From "Dry" by Neal Shusterman and Jarrod Shusterman

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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