'feud' originates from Old High German, specifically the word 'fehda' (also attested as 'fehdu'), where the root meant 'hostility' or 'dispute'.

'fehda' passed into Middle English as forms like 'fehde' or 'feude' and eventually became the modern English word 'feud'.

Initially, it meant 'hostility or armed conflict'; over time it evolved into the modern sense of 'a prolonged quarrel or vendetta' and the verbal sense 'to carry on such a quarrel'.