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 agreement Barnett reached with LaBeouf “contained a deficient and unlawful NDA that is unenforceable,” under California’s Stand Together Against Non-Disclosure Act, according to the complaint.

From Los Angeles Times • Mar. 26, 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

“It is a very deficient law,” said Francisco Monaldi, a Venezuelan who directs the Latin America energy program at Rice University’s Baker Institute for Public Policy.

From The Wall Street Journal • Jan. 22, 2026

LPA is the rainfall or snow recorded over a region over 30 to 50 years and use its average to classify current weather as normal, excess or deficient.

From BBC • Jan. 11, 2026

I stumbled to my feet; my leg dragged, deficient in its circulation.

From "The Astonishing Life of Octavian Nothing, Traitor to the Nation, Volume I: The Pox Party" by M.T. Anderson

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