'alrune' originates from Old High German, specifically the word 'alrūna', where 'al-' meant 'all' and 'rūna' meant 'secret' or 'mystery'.

'alrūna' transformed into the Middle High German word 'alrūne', and eventually became the modern English word 'alrune'.

Initially, it meant 'a secret or mysterious plant', but over time it evolved into its current meaning of 'a mythical or magical plant'.