'affrightfully' originates from Middle English, specifically the word 'affright,' where 'af-' meant 'to' and 'fright' meant 'fear.'

'affright' changed from the Middle English word 'affrighten' and eventually became the modern English word 'affright.'

Initially, it meant 'to cause fear,' but over time it evolved into its current meaning of 'in a manner that causes fear or terror.'