'barbarian' originates from Greek, specifically the word 'barbaros', where 'barbar-' meant 'non-Greek, foreign; speech perceived as unintelligible (imitative "bar-bar")'.

'barbaros' passed into Latin as 'barbarus', then into Old French as 'barbare' and into Middle English ultimately forming the modern English 'barbarian'.

Initially it meant 'foreigner' or 'one who speaks unintelligibly'; over time it evolved to mean 'an uncivilized or brutal person' in English.