• A short delay of a merchant ship entering port prior to receiving her documents.
  • A harbor restriction placed on a vessel that has an outbreak of an infectious disease aboard or has arrived from a country that is known to have infectious diseases prevalent.


17th century. From Old French and from Latin, Quadragesima, meaning the Forty Days.


While under quarantine, a ship must fly the Q flag in the International Code of Signals to indicate her status. Her crew may not land until the infectious period (forty days for the plague) has passed or she is certified as free from disease. These quarantine laws were created at the Council of Health in Venice in the 14th century.


Kemp, P. (1994). The Oxford Companion to Ships and the Sea. Oxford University Press.

Rogers, J.G. (1985). Origins of Sea Terms. Mystic Seaport.