Jackstaff
A jack staff is a small vertical spar on the bow of a ship or smaller vessel on which a particular type of flag, known as a jack, is flown. The jack staff was introduced in the 18th century.
A jack is typically flown from military vessels while at anchor or moored pierside, but not while underway. Civilian vessels have been known to fly the jack of the nation of their homeport, also from a jack staff, while moored or at anchor.
