Black's Law Dictionary (2nd edition)dictionaries

Quarantine

A period of time (theoretically forty days) during which a vessel, coming from a place where a contagious or Infectious disease is prevalent, is detained by authority in the harbor of her port of destl-nation, or at a station near it, without being permitted to land or to discharge her crew or passengers. Quarantine is said to have been first established at Venice in 1484. Baker, Quar. 3

Source: Black's Law Dictionary 2nd Ed (1910)