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Showing results for deficient. Search instead for deficien.
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.

“Our animals and us are actually super deficient in light, especially the most healing wavelengths that we have,” says Jackie Jolie, CEO of AnimaSol.

From The Wall Street Journal • Jan. 28, 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

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

“I am happy you approved,” said Emma, smiling; “but I hope I am not often deficient in what is due to guests at Hartfield.”

From "Emma" by Jane Austen