ENGLISH
REFERENCE

deficiency

n. C / U
C1 Advanced Oxford US //dɪˈfɪʃənsi// UK //dɪfˈɪʃənsi// de·fi·cien·cy

n. a lack of something that your body or a system needs to work correctly. It can also mean a weakness or a part of something that is not good enough.

n. a lack or shortage of a required substance or quality; a failing or shortcoming in a system or person. Often used in medical or technical contexts to describe insufficient levels of nutrients.


SIMPLE

A vitamin deficiency can make you feel very tired.

CONTEXTUAL

The doctor ordered blood tests to check if a mineral deficiency was causing her frequent headaches.

COMPLEX

The audit highlighted a significant deficiency in the company's internal security protocols, suggesting that current measures were insufficient to prevent data breaches.

Synonyms
Antonyms
Origin

From deficient + -cy. Compare Latin dēficientia.

Usage

Uncountable when referring to the general state of lacking something; countable when referring to specific types or instances of failure.

Pitfall

a deficiency about irona deficiency of ironThe noun typically takes the preposition 'of' to indicate what is lacking.

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