'self-flagellant' originates from Latin, specifically the word 'flagellare,' where 'flagell-' meant 'to whip.'

'flagellare' transformed into the French word 'flagellant,' and eventually became the modern English word 'flagellant' through Middle English.

Initially, it meant 'to whip oneself,' but over time it evolved into its current meaning of 'a person who punishes themselves for spiritual reasons.'