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.

"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

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 a randomized clinical trial, magnesium increased vitamin D in people who were deficient, while reducing levels in those who already had high amounts.

From Science Daily • Dec. 30, 2025

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

From "Dry" by Neal Shusterman and Jarrod Shusterman

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