'sadist' originates from French, specifically the word 'sadisme,' which was derived from the name of the Marquis de Sade, a French nobleman known for his libertine sexuality.

'sadisme' transformed into the English word 'sadist' in the late 19th century.

Initially, it referred to the practices of the Marquis de Sade, but over time it evolved into its current meaning of deriving pleasure from others' pain.