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.

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

Meanwhile, older people think I’m somehow financially deficient because I rent.

From The Wall Street Journal • Jan. 20, 2026

Lacking one of their top players with guard Skyy Clark sidelined by a hamstring injury, the Bruins also were deficient in many other areas.

From Los Angeles Times • Jan. 6, 2026

In the thirteen years since she’d left Moton High School, the deficient building had passed from being merely overcrowded to packed beyond reasonable measure.

From "Hidden Figures" by Margot Lee Shetterly

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