Definitions

deficiency

[dih-fish-uhn-see] / dɪˈfɪʃ ən si /

NOUN

imperfection, inadequacy

Synonyms

STRONGEST

dearth defect failing failure fault flaw frailty glitch insufficiency lack scarcity shortage shortcoming weakness

STRONG

absence bug defalcation default deficit demerit dereliction loss need neglect paucity privation scantiness sin want

WEAK

inability to hack it insufficience

Antonyms

STRONGEST

abundance advantage enough excess perfection plenty strength strong point success sufficiency surplus

STRONG

accomplishment achievement

WEAK

adequacy faultlessness satisfaction superfluity

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.

This is why B12 deficiency is taken seriously.

From Science Daily • May 27, 2026

The findings suggest the tropical fruit juice could become a useful addition to nutrition programs aimed at preventing iron deficiency anemia in regions where the condition is widespread.

From Science Daily • May 27, 2026

They do, however, suggest that the current definition of B12 deficiency may be too blunt for brain health.

From Science Daily • May 22, 2026

"Revisiting the definition of B12 deficiency to incorporate functional biomarkers could lead to earlier intervention and prevention of cognitive decline."

From Science Daily • May 22, 2026

Where there are fewer, the deficiency may be remedied by collecting and distributing the baglike cocoons containing the eggs.

From "Silent Spring" by Rachel Carson

Vocabulary lists containing deficiency

Freak the Mighty

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Flowers for Algernon

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Paltry Parlance: Synonyms for "Few"

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