'emir' originates from Arabic, specifically the word 'amīr', where 'amīr' meant 'commander' or 'prince'.

'amīr' was adopted into Medieval Latin as 'emir' and then into Old French as 'emir', eventually becoming the modern English word 'emir'.

Initially, it meant 'commander' or 'military leader', but over time it evolved to refer more broadly to a ruler or prince in Islamic countries.