'inmate' originates from Middle English, specifically the word 'inmate,' where 'in-' meant 'inside' and 'mate' meant 'companion.'

'inmate' changed from the Middle English word 'inmate' and eventually became the modern English word 'inmate'.

Initially, it meant 'a person who shares a dwelling,' but over time it evolved into its current meaning of 'a person confined to an institution.'