The word leper was historically used to refer to someone who suffered from leprosy, a bacterial illness that affects the
nerves, skin, and respiratory tract. Because leprosy was thought to be highly contagious, the word leper also came to be used more generally to mean "an outcast" or "a person to be avoided."
Jesus cleansing a leper is one of the miracles of Jesus. The anecdote is found in all three of the Synoptic Gospels: Matthew 8:1–4, Mark 1:40–45 and Luke 5:12–16.
King Baldwin IV was known as the Leper King due to his severe affliction with the illness.
The Order of Saint Lazarus of Jerusalem was a hospitaller monastic order that specialized in the care of lepers.