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.

FCC Chairman Brendan Carr said in a statement Thursday that Disney filed its applications to renew its broadcast licenses only after the company was told its previous answers were “disingenuous, deficient and improper.”

From Los Angeles Times • May 28, 2026

Vomiting was only reported in the deficient group, although researchers said the difference was too small to be considered statistically significant.

From Science Daily • May 20, 2026

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

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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