# improper

> English word · Adjective · IPA /ɪmˈpɹɒp.ə/ · frequency rank #13,366

## Definitions
1. Unsuitable to needs or circumstances; inappropriate; inapt.
2. Not in keeping with conventional mores or good manners; indecent or immodest.
3. Not according to facts; inaccurate or erroneous.
4. Not consistent with established facts; incorrect.
5. Not properly named; See, for example, improper fraction.
6. Not specific or appropriate to individuals; general; common.
7. Of a complex random variable, correlated with its conjugate.

## Etymology
From Middle French impropre, from Latin improprius (“not proper”), from in- + proprius (“proper”). By surface analysis, im- + proper.

## Easily confused with
- **improve** (https://plainspell.com/en/vs/improper-vs-improve)
- **improved** (https://plainspell.com/en/vs/improper-vs-improved)
- **improperly** (https://plainspell.com/en/vs/improper-vs-improperly)

## Common misspellings (12)
`immproper`, `imporper`, `impproper`, `improepr`, `improperr`, `impropper`, `impropre`, `imprpoer`, `imprroper`, `imrpoper`, `ipmroper`, `miproper`

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