# insanity

> English word · Noun · IPA /ɪnˈsænɪti/ · frequency rank #10,870

## Definitions
1. The state of being insane; madness.

## Etymology
A three-part word (root 'sane', prefix 'in-' meaning 'not', suffix '-ity', meaning 'the state of'). Derived from Latin precursory equivalents. Two possible candidates for construction order:
* insane + -ity: īnsānus (“unhealthy; insane”) + -itās
*: Latin īnsānus (“unsound in mind; mad, insane”), from in- + sānus (“sound, sane”). Modern forms of roots: in- + sane
* in- + sanity: in- (“lacking; without”) + sānitās (“health; sanity”)
*: Latin sānitās (“sound in mind; sane”), from sānus + -itās. Modern forms of roots: sane + -ity

## Easily confused with
- **infinity** (https://plainspell.com/en/vs/infinity-vs-insanity)
- **insanely** (https://plainspell.com/en/vs/insanely-vs-insanity)

## Common misspellings (12)
`inasnity`, `innsanity`, `insainty`, `insanitty`, `insanityy`, `insaniyt`, `insannity`, `insantiy`, `insnaity`, `inssanity`, `isnanity`, `nisanity`

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