Flagellant

noun

1. One who whips, especially one who scourges oneself for religious discipline or public penance.
2. One who seeks sexual gratification in beating or being beaten by another person.
3. Given to flagellation, or the use of the rod; flagellating.
4. One who whips or scourges himself for religious discipline; specifically, in history, one of a body of religious persons who believed they could thus appease the divine wrath against their sins and the sins of the age.
5. One of a fanatical sect which flourished in Europe in the 13th and 14th centuries, and maintained that flagellation was of equal virtue with baptism and the sacrament; -- called also disciplinant.