'birthright' originates from Old English, specifically the word 'gebyrdrīht,' where 'gebyrd' meant 'birth' and 'rīht' meant 'right.'

'gebyrdrīht' transformed into the Middle English word 'birthright,' and eventually became the modern English word 'birthright.'

Initially, it meant 'the rights one is born with,' and this meaning has largely remained the same in modern usage.