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.

B12 deficiency becomes more common with age, partly because the stomach may produce less acid, which is needed to release B12 from food.

From Science Daily • Jun. 6, 2026

This is why B12 deficiency is taken seriously.

From Science Daily • May 27, 2026

Iron deficiency anemia is especially common among pregnant women and adolescent girls in many developing countries.

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

In whose view inadequacy was mere idiosyncrasy, a character trait rather than a deficiency?

From "Sula" by Toni Morrison

Vocabulary lists containing deficiency

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