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

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

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

From Science Daily • Mar. 27, 2026

Iran, which is an IMO member but does not sit on its council, hit out at the declaration, branding it "one-sided, unfair, inaccurate and legally deficient".

From Barron's • Mar. 19, 2026

It seems pointless to maintain that Aristotle and his followers were deficient in common sense, or deficient in experience of how the world goes.

From "The Invention of Science" by David Wootton

Vocabulary lists containing deficient

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