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 vitamin D deficient group also required more opioid medication.

From Science Daily • May 20, 2026

Being truly deficient in B6 is rare, although sometimes levels can be a bit low, often alongside a lack of other B vitamins, such as B12, which can leave you feeling tired and nauseous.

From BBC • Apr. 22, 2026

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

Deere leverages AI to help farmers cut costs—by reducing labor required to operate equipment, minimizing wasted crop chemicals, and applying fertilizer more precisely where soil nutrients are deficient.

From Barron's • Feb. 2, 2026

But I do know we’re deficient in some way.

From "Tuesdays with Morrie" by Mitch Albom

Vocabulary lists containing deficient

Tuesdays with Morrie

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50 Words from Jane Austen's "Pride & Prejudice"

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