# deficiency vs deficient

> English confusable word pair

## The two words

### deficiency
*noun · IPA /dɪˈfɪʃənsi/ · frequency rank #12,220*
Inadequacy or incompleteness.

### deficient
*adjective · IPA /dɪˈfɪʃənt/ · frequency rank #18,801*
Lacking something essential; often construed with in.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/vs/deficiency-vs-deficient