From Late Middle English rasen, rasyn (“to rage; to enrage (?)”), probably from Middle Dutch râsen, râzen (“to be extremely angry, rage; to be mad, rave; to talk nonsense; of a dog: to be rabid”), from Old Dutch *rāson (modern Dutch razen), from Proto-West Germanic *rāsōn (“to rush”), Proto-Germanic *rēsōną (“to rush”), ultimately from Proto-Indo-European *h₁reh₁s- (“to flow; to rush”).
cognates
* Swedish rasa (“rage”)