"house for reception of lepers and diseased poor persons," 1540s, from Italian lazareto "place set aside for performance of quarantine" (especially that of Venice, which received many ships from plague-infested districts in the East), from the Biblical proper name Lazarus. Meaning "building set apart for quarantine" is c. 1600 in English. The word in Italian was perhaps influenced by the name of another hospital in Venice, that associated with the church of Santa Maria di Nazaret.
