# J-cat

> English word · Noun

## Definitions
1. A mentally unstable inmate.
2. One who behaves in an erratic or overly excited manner.

## Etymology
Short for J-Category (also Category-J), a former designation used for mentally ill prisoners in the California State Prison System.

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