'gaol' originates from Anglo-Norman and Old French, specifically the word 'gaiole' (from Late Latin 'gabiola'), where 'gabiola' meant 'little cage'.

'gaol' changed from the Anglo-Norman/Old French word 'gaiole' (Middle English forms included 'gayol' and 'gaol') and eventually became the modern English word 'gaol' (with the variant spelling 'jail' later established, especially in American English).

Initially, it meant 'little cage' or 'enclosure', but over time it evolved into its current meaning of 'a place of confinement; jail'.